FR2872940A1 - HETEROGENEOUS DATABASE INTERROGATION SYSTEM AND INTERROGATION METHOD - Google Patents

Abstract

The present invention relates to a system and method for interrogating heterogeneous databases. According to the invention, the original set (1) of heterogeneous databases is decoupled from the interrogation system by means of: • A module (3 ) organizer of the data to associate them by reference to a plurality of domains and a plurality of metadomains; • a response data generation and interrogation module (4) which includes a search metamotor for managing request forms and producing response data.

Description

"System for interrogating heterogeneous databases and

  The present invention relates to a system and method for interrogating heterogeneous databases.

  In the state of the art, there are known heterogeneous database management systems particularly in the field of medical records. Reference is made in particular to the patent WO-A1-03 / 065251 which allows the exchange of information between heterogeneous databases by means of the manipulation of a semantic equivalence operator. In this state of the art, semantic equivalences are sought on concepts described in the data of two distinct bases. The purpose of this equating operation is to work on queries at different levels of granularity so that one query among multiple databases can reconstruct consistency between data records of different types.

  In addition, the management of very large databases, and very large heterogeneous databases has been an important development topic for several years and several publications take stock of these developments. In US-A-2002/0156756, in the name of Stanley, there is described a method and structure of molecular object data that makes it possible to manage heterogeneous data environments. In this document, the software application described allows to unify the user's presentation of various data. It describes a set of procedures that make it possible to achieve: - management of the state of activity and content in persistent data; - a functional integration is a data exchange between the databases, and applications and the different component is interfaces.

  Such a solution requires that the set of data be recomposed, while the invention aims precisely to process existing data and maintaining pre-existing database management systems that are not directly modified by the invention.

  In US-A-2003/176929, on behalf of Gardner, there is described a user interface that includes a data source set and a processing section that allows a user to select a processing that depends on search results. among the data so as to produce a treatment result. In this state of the art, the heterogeneity of the data is a factor that reduces its ability and efficiency of search processing.

  In US-A-6,009,422, in the name of Cicarelli, there is described a method and system for performing a semantic translation or a search translation that uses a generalized search language in a plurality of heterogeneous databases. In the document, the efficiency depends on the generalized grammar that would translate into sentences contained in a generalized search language, which the invention overcomes.

  In US-A-5,552,403, in the name of Lin, there is described a method and system for rewriting databases without reducing the ability to exploit the database when rewritten. However, this document leads to a modification of the heterogeneous databases to allow their unified interrogation. The advantage of the present invention is to allow the original databases to be kept in the state they are in and at the same time to be able to modify them without disturbing the interrogation capabilities of the users.

  Such a state of the art only partially addresses the problem of exploiting heterogeneous databases. Indeed, large databases lead to the formulation of a considerable number of queries or even different classes of queries. The system for interrogating heterogeneous databases, presented in the document US Pat. No. 5,552,403, does not allow a flexible query by persons unfamiliar with the structure of the databases used.

  The present invention also provides an effective solution to this problem of the state of the art.

  An advantage of the invention is that it makes it possible to reduce the total cost of acquisition of a heterogeneous database query system by reusing the maximum of existing computer infrastructures, both hardware and software.

  Another advantage of the invention is to make it possible to offer new possibilities of use to the users of a heterogeneous database interrogation system while reducing the cost of development and maintenance of the basic interrogation system. heterogeneous data. Such a gain is possible in terms of management time of the interrogation system and human resources compared to an information system that is constantly evolving within an institution or company.

  Another advantage of the invention is to allow the use of technologies common to the Unix world and the Windows world which ensures easy migration from one world to another. It also follows that it is possible to perform evolutions based on the software components characteristic of these two worlds, and when these components evolve, to benefit the interrogation system of heterogeneous databases of the invention.

  Another advantage of the present invention is to allow automated generation of the computer interface between a user of the interrogation system of the invention and the mass of the searchable data without the user needing to know the structure of the heterogeneous data. nor a particular database management language.

  Another advantage of the invention is that it makes it possible to benefit from a computer interface, in particular of the web type, open to the outside, which interfaces with other tools of the intranet, and which presents the simplicity of use features of the web interfaces.

  Another advantage of the invention is that it makes it possible to rapidly execute queries on large masses of heterogeneous documents and to cross these data in a linear calculation time with respect to the mass of the data. With this speed of execution, users can rephrase and / or refine their questions as many times as necessary before saving the queries and their results.

  Another advantage of the invention is that it enables users to share pluridisciplinary type of knowledge that can be interrogated in the heterogeneous database query system, which facilitates the search for computer solutions on the one hand and the search for solutions on the other. problems characteristic of the business practiced in the enterprise in which the heterogeneous database query system of the invention is installed.

  In order to solve the aforementioned problems and to provide the announced advantages, the invention relates to a system for interrogating heterogeneous databases of the type comprising: a set of databases, all or some of which may have their own system; query, a means for generating interaction between a user and a plurality of data of the database set.

  According to the invention, the means for generating an interaction between a user and a plurality of data of the set of databases comprises: É A data organizing module for associating them by reference to a plurality of organization entities; A response data generation and interrogation module that includes means for generating query forms and generating response data.

  According to one aspect of the invention, the interrogation system comprises a data storage module and a means of connection to said set of data at least on copy dates and in that the data storage module comprises: - a relational database part; a part of tree data.

  Finally, the invention also relates to a method of interrogating heterogeneous databases which is characterized by two main phases: a first phase of organization of the data by an administrator and executed on the basis of at least one model of structure data to query; a second phase of interrogation of the data by a user and executed on the basis of forms generated according to the organization of the data determined during said first phase of organizing the data.

  Other advantages and features of the present invention will be better understood with the aid of the description and the appended figures among which: FIG. 1 represents a block diagram in a particular embodiment of the interrogation system of the invention ; FIG. 2 represents a diagram of the data deposit unit of the embodiment of the interrogation system of FIG. 1; FIG. 3 represents a diagram of the data structuring unit of the embodiment of the interrogation system of FIG. 1; FIG. 4 represents a metamodel of data adapted to a hospital information system in an exemplary application of the interrogation system of FIG. 1; FIG. 5 represents a block diagram of the interrogation unit of the embodiment of the interrogation system of FIG. 1; FIG. 6 represents part of a means implemented in the data organization module; FIG. 7 represents an embodiment of the interrogation system represented during the execution of a query request by a user.

  In Figure 1, there is shown a block diagram of a heterogeneous database query system according to the invention. In Figure 1, the databases 1 pre-exist the establishment of the interrogation system of the invention. They can also be created or augmented, updated and undergo any other maintenance operation directly using the interrogation system of the invention.

  The database interrogation system of the invention comprises three main modules: a module 2 for depositing data from the set of databases; a module 3 for organizing the data so as to execute a structuring according to organizational entities as will be explained later; an interrogation module 4 which enables users 5 to use the interrogation system by producing at least one interrogation and receiving in response a set of interrogation results.

  According to an essential aspect of the invention, the databases 1 can be exploited separately from the interrogation system of the invention by the database management systems that already exist in the state of the art or other again. In particular, the advantage of the invention is to provide a unifying means of heterogeneous databases whose cooperation is difficult because of the differences between the various different data structures, and between the various interrogation languages. However, the invention will not require the disappearance of the database management systems, in particular relational databases, which allow locally in one of the databases 1, to maintain, according to local constraints, the content and data structure.

  In order to allow operation that does not interfere with the operation of such independent management systems of the invention, the interrogation system of the invention comprises the data storage module 2 which makes it possible to repatriate the data in the form of local copies. , or in the form of references such as hypertext links. The data thus deposited is available to the rest of the interrogation system.

  The repatriation of data can be done during periods of non-use of all the data 1, for example outside working hours in a conventional office organization. It also follows that the access of a user of the interrogation system of the invention to data deposited in the organizational module 2 does not disturb a modification of a database of the set of data 1 by a producer. In one embodiment, the repatriation of data is, at least partially, performed as a reference for each accessible data unit, as a reference to the address of a document on a web server.

  When the data is deposited in the module 2 for copying or depositing data, an organization module 3 executes a structuring of the data into organizational entities. In one embodiment of the invention, the organization entities are metadomains and domains that reproduce a characteristic pattern of acyclic trees, a scheme that will be described later. Such an organization is conducted by an organization administrator, such as the administrator Ad, who has an RL1 connection to the organization module 3. Such an organization administrator can access the data, and particularly the data copied into the document. module 2, so that it is able to achieve at least an initial phase of structuring the data. To this end, it has an access interface IG2 for accessing the data storage module 2 and an access interface IG1 for access to the organization module 3 so that organization entities of the copied data are produced as well as it will be described later. The administrator Ad is connected to the two resources IG1 and IG2 by a computer link network RL1 which can be autonomous from the information network of the company, particularly if the administration function of the organization module 3 is outsourced to a specialist outside the entity or enterprise in which the invention is implemented.

  According to one aspect of the invention, the data storage module 2 and / or the data organization module 3 also comprises a client server type entity, in particular of the web type, to access data stored in data storage trees. directory.

  In another embodiment, the data organization administrator Ad can access a user-established request management resource 5 using another RL2 link to be in contact with the users. of the entity or enterprise in which the interrogation system of the invention is implemented. Such an organization administrator Ad then has a resource for cooperating with the users during the organization of the data for the production of the organizational entities implemented in the organization module 3 and / or a resource for exploiting data. query statistics to modify the organizational entities to optimize the interrogation of the data storing module 2 in terms of the establishment time of the query and / or the use of the caches as well as it will be described later. An organization administrator therefore constitutes a technical entity that can manage one or more interrogation systems according to the invention, independent or interconnected for example by means of a Web connection.

  Once the data has been deposited, access by a user 5 to the repository data in module 2 is done via interrogation module 4 which exploits a form generator and a search metamotor using structural elements. which correspond to the organization entities of the organization module 3. The search metamotter, as will be described later, exploits several search engines to execute at least one query for interrogating the data of the data repository 2.

  When the organizational entities are metadomains and domains, the structural elements of the query forms are metacleans and primary keys which correspond, during their construction 9, to the structuring according to the acyclic tree described above.

  In one embodiment, the set of users 5 is interconnected via a local network and / or a computer TV network, such as the Internet, or an intranet network that allows them access 8 to the interrogation system itself.

  In particular, at least one (not shown) of the user machines 5 is dedicated to the administration of the heterogeneous database query system of the invention, and its role will be explained later in the text.

  In Figure 2, there is shown a particular embodiment of the interrogation system of Figure 1.

  In Figure 2, the same elements as those of Figure 1 have the same reference numbers. The data deposition module 2 executes, during the operation 6 (FIG. 1), a repository of the data of the set of data 1.

  Databases and other data, such as references to referenceable data of the data set 1, and arranged in the set of data sets 1, are deposited in the data storage and organization module 2. In a particular embodiment, the data storage module 2 is composed in two parts which are respectively: a part of relational databases 80; A part of tree data In a particular embodiment, the relational database part 80 of the deposition module 2, dialog with a relational database query system of SQL type implemented in a module 84 belonging to the unit 3 of data organization.

  The tree data portion 81 dialogs with a file tree server system using web server technology such as Apache, IIS, and so on. and implemented in a module 85 belonging to the data organization unit 3. In the context of the invention, the tree data are data or units of data structured in tree as it is known in the state of the art.

  According to the invention, the data repository is executed as it is in a data box consisting of a storage space based on hard disks that can be distributed over a computer network, of the Internet type or intranet type. The data are therefore not modified or even restructured during the deposit.

  Continuing with the description of FIG. 2, it can be seen that the original data set 1 comprises four different types of databases which are in particular: document databases 70 among which can be found particular databases created by the Lotus Notes application (TRADEMARK); relational databases 72 among which can be found in particular the databases created by the Oracle applications (TRADEMARK), Microsoft SQL Server io (registered trademark), Sybase, MySQL, etc. ; - databases consisting of websites on intranets and / or on an Internet network 74; and - data 79 recorded in file trees such as office documents and which are for example on shared storage volumes or connected by a teleinformatic network on which are connected different machines of the users of the interrogation system of the computer. 'invention.

  To deposit or supply the data box 80 and / or 81 of the data storage unit 2, the interrogation system of the invention has a plurality of computing resources capable of transferring the data. . In particular, one finds successively in the example of application of FIG. 2: a middleware type application such as Notrix (DEPOSITED TRADEMARK), which makes it possible to connect the document databases 70 to the relational part 80 of the data box 2; a middleware application like Datastage (DEPOSITED TRADEMARK), which makes it possible to connect the relational databases 72 to the relational part 84 of the data box 2.

  a method developed according to a C ++ platform for importing websites 75 which makes it possible to transfer the websites to 74 in the relational part 80 of the data box 2; a method developed according to a C ++ platform for importing web sites into a tree structure in the tree part 81 of the data box 2; an import method developed according to a C ++ platform for importing tree data in the tree part 81 of the data box 2; a method for importing web-type tree data from the tree part 81 of the data box 2 to the relational part 80 of the same data box 2; a method for importing text-type tree data from the tree part 81 of the data box 2 to the relational part 80 of the data box 2.

  Each of these applications or import methods makes it possible to copy the data contained in the data system 1 to the data storage unit 2.

  The reproduction of the initial data structure in the data set 1 ensures, with the aid of the relational database query system 84, a useful and efficient exploitation of the data thus structured. There is no loss of information in the data box, nor data that can not find their place in a unified data model.

  In addition, the structural identity between the production system and the interrogation system, which will be studied later, makes it easier to understand and thus to formulate queries.

  Due to the copying in the data storing unit 2, the data supply is decoupled from the organization of the data set in a conceptual model. But a unified model, invented after the production of the data of a given production system, only works correctly in theory. In practice, it is necessary to make readjustments that mobilize at least one administrator from each database of the set of databases 1.

  Moreover, the distribution between data repository on the one hand and data organization on the other hand leads to sending the interrogation task to an independent tool, which does not intervene during the supply phase. data. It is thus possible, which is essential in the case of a company or a group of companies having many heterogeneous data management systems, to modify one or other of the data models during their lifetime. own operation, without the interrogation function of all data 1 is disturbed by such a change.

  In another embodiment, it is possible not to have a data storage module 2, but instead to work directly on the data set 1.

  The method used to operate the interrogation system of the invention will now be described. It comprises at least two phases that can be repeated. The method comprises: a first phase of organization of the data by an administrator and executed on the basis of at least one structure model of the data to be interrogated; a second phase of interrogation of the data by a user and executed on the basis of forms generated according to the organization of the data determined during said first phase of organizing the data.

  In the first organization phase, a first data organization step is determined based on at least one data structure model to be interrogated so as to bijectively associate at least one real data set with an element. request. Then, a second step is executed in which at least one form is generated with form elements associated with query elements.

  In the second phase, when he wishes to conduct a query, a user selects a form and produces at least one request on his database, in particular by selecting and arbitrarily setting each form element. Then, in a second step, the user's request is forwarded to a query analysis module according to the organization elements so that the user's query query is decomposed according to the elements. request. In a third step, the data organization determined during the first phase is traversed according to a directional diagram which is deduced from it and the references of the responses located in the interrogated data set are then recorded. Once the answers are recorded, in a fourth step, the answers are then collated so as to be produced to the user in a response form which then generates a final result.

  Referring now to FIG. 3, the operation of a particular embodiment of the data organization module 3 will be described. The part of the interrogation system of the invention which is in relation with the user essentially comprises a user interface 10 connected by a bidirectional channel 20, 21 to a request formulation module 11 connected by a bidirectional link 22 to the module. organization 3.

  The data organization module 3 works according to several levels of organization. The top level of organization is the metamodel of data. Each metamodel is made up of metadomains, then query domains that are built on the basis of the form generator 11. Metadomains and domains are linked together through a data model. The query domains are the basic entities in direct relation to the data sources that are in the data storing unit 2.

  The metamodel is a data structure based on a graph or acyclic directed tree, composed of edges, nodes and leaves that appear in particular in Figures 3 and 4. In the metamodel, an edge corresponds to a model, a node corresponds to a metadomain and a leaf corresponds to a domain. Each metamodel implemented in the interrogation system of the invention, and each time it is implemented in a particular application of the invention, is a particular class of acyclic directed tree of type DAG io which contains at least one vertex . A node is a starting point for navigating the entire tree, but is itself inaccessible from other nodes of a deeper level.

  Referring now to FIG. 4, an implementation of a simplified metamodel applied to a hospital medical information system will be described.

  The starting metadomain is constituted by the patient metadomain 40 which will be detailed elsewhere. In Figure 4, and metadomains are represented by an oval while the domains are represented by rectangles. The metamodel of the information system is composed of a four-level graph. After the initial level, the second level includes three metadomains 42 hospitalizations, 43 pathology samples, 45 biochemistry samples. In the second level, the information system comprises two domains which are the domain 41 of the consultation reports 44, the radiology report. The third level comprises a single metadomain and seven domains which are respectively: metadomain 46 of the patient's medical unit passages; the domains 47 of the hospitalization reports, the microscopic files 48, the tumor bank 49, the diagnostic chart 55 and the flow cytometry reports 51, the pathology report 52 and the haematheca 53.

  The edges of the graph make it possible to associate the metadomain of the hospitalizations 42 with the metadomain 46 and the domain 47, the metadomain 43 of the pathology samples with the four domains 49, 51 and 52, the metadomain of the samples of biochemistry 45 with the domains 50 and 53.

  The fourth level of the metamodel of the hospital information system is composed of the three domains related to the metadomain 46 and which are respectively: the domain 54 of the passages; io - domain 55 of the diagnoses; - domain 56 of the acts.

  When the administrator, during the first phase, first step of the method of the invention, determines the organization of the searchable data, he determines the metadomains among: - the most important entities that the company that would operate the system of interrogation of the invention manipulates during its activity. For example in a bank of the essential entities are the customer, the bank account, the agencies, etc. In a manufacturing plant, important entities are manufactured products, suppliers, customers, etc. In an anti-cancer center, important entities are the patient, the hospitalization, the tumor to heal, etc. The administrator of the interrogation system of the invention uses a metadomain management means that enables him to generate the metadomains that are suitable for his institution; - The entities to which the users of the interrogation system would systematically report any query results if the calculation time allows.

  One can distinguish between two types of organizational entities depending on whether or not it depends on another essential entity. Metadomains not dependent on any other entity are at the top of the directed acyclic graph representative of a metamodel, while other metadomains are the nodes of the metamodel defined from the first entity. In the same way, the administrator of the interrogation system of the invention has in the interrogation system of the invention a metamodel creation means provided with a means for prioritizing the metadomains according to whether they are independent or dependent on other metadomains. In most applications of the interrogation system of the invention it has been found that the number of independent metadomains is generally less than five while most activities of the same enterprise are limited to fifteen dependent metadomains.

  In the interrogation system of the invention, the domain is the basic entity which makes it possible to directly interrogate data in the set 1 or indirectly a set of data deposited in the data storage unit 2. Each domain is registered in Module 3. The domain as a base unit consists of a set of computer objects and is fully autonomous so that it contains all the resources and information needed to query a data source. It includes: - a connectivity resource to the data source as a relational database query system; - all metadata concerning the data source, the characteristics of the data, etc. - a visual interface allowing a user to formulate questions about the data.

  FIG. 6 shows in a diagram the articulation between a domain and a metadomain as well as the architecture of the means arranged in particular in the data organization module 3 for organizing the data under the action of an administrator. Ad organization, then to query the data organized under the action of a request of a user 5. According to the invention, the prior analysis of the data of the set 1 was made to form a metamodel of the set of data 1 seen by the interrogation system, so that a plurality of metadomains is defined with dependency relations arranged according to an acyclic directed tree stored in a suitable memory of the data organization module 3.

  Each node of the acyclic directed tree 90 for which a dependency relationship is down is a metadomain, while a domain is a terminal node of the acyclic directed tree 90.

  As a result, each node of the tree stored in the memory 90 of the organization module 3 of the data can be represented by: a metadomain 91 defined by a name :: Name and a metacle :: Metacle denoted by a relation in the tree referred by mk; a domain 92 defined by a name :: Name and a primary key :: Primary_key denoted by a relation in the tree referred by Pk.

  Each domain 92 is, as indicated above, coupled to a connectivity resource :: connectivity 93, a viewing visualization resource :: visualization 94 and a pointing resource on the data model :: model 95.

  A metadomain analyzed by the resource 91 of the data organization module 3 thus makes it possible to point each unit of data of the real data set 1 or of its copy in the deposition module 2 as a point of an intermediate node 96 of the acyclic directed tree 90. The point is referred by the mk metacle. Similarly, an end node 97 of the acyclic directed tree 90 refers to a data unit of the real data set 1 or its copy in the deposition module 2 as a point pointed by the primary key Pk.

  Each point of the representative node of a meta-domain 96 is connected by the connectivity resource 93 by: a first bijective analysis application 99 which is traversed when a request element is returned from the request module 4 so as to reach to the address of a document or any unit of data referenced by the interrogation system through the domain 97 and the domain management resource 92; a second bijective response application 98 which makes it possible to trace the reference of the data unit responding to the request part during the construction of the response.

  In a practical embodiment, a domain corresponds to a relational table or to a main relational table and to several secondary relational tables for example having relations of 1 to N or of N to 1 (in the case of a thesaurus) with the main table.

  The interrogation system of the invention comprises a means for generating domains that is to say computer objects comprising: a resource of connectivity towards the data source; a set of metadata; - a visual interface of questions about the data associated with the domain.

  In the interrogation system of the invention, the model is an entity that makes the connection between the concrete data of the domains and the different implications of metadomains. A model with essentially four components that vary according to the type of model, but whose principle remains similar. The four components are: - pk: the set of primary keys of the domain; - mk: the set of corresponding metaclés; pk_mk: the set of links from primary keys to corresponding metaclasses; - mk_pk: the set of links ranging from associated metacleans to primary keys.

  In a practical embodiment of the interrogation system of the invention, model-based management means makes it possible to create, update and manage the above-mentioned components of a model so as to configure a bijective relation which makes it possible to point from a metadomain to a domain. Subsequently, in a higher order of organization, a particular model of data is integrated with its pairs of lo bijective relations.

  The same scheme is applied to configure the edge of the acyclic directed graph from a parent metadomain to a child metadomain. For this purpose, in a practical embodiment of the interrogation system of the invention, model management means makes it possible to create, update and manage the aforementioned components of a model so as to configure a relationship. bijective which makes it possible to point from one metadomain to another metadomain in a model that is to say, to configure a particular edge of the acyclic graph directed from a metadomain (represented by an oval in FIG. another metadomain (represented by an oval in Figure 4).

  The heterogeneous data interrogation system of the invention combines several tools that give the user the means to centralize, organize and / or query the data arranged in the data storage module 2 or directly in the data set 1. For this purpose, the database interrogation system of the invention comprises one or more tools, among which: a processing unit configured as a man-machine interface comprising a web-like visual interface, with interrogation forms; and tables presenting the results, as well as a query formulation module (GEN_FORM, Figure 5), which makes it possible to translate the requests of the users into different computer languages on the one hand to circulate the requests among the search engines able to query the resources of modules 1 or 2 data or data deposit, on the one hand, and in human language on the other hand notamme nt to produce the answers to the user; a query metamotter (MM, FIG. 5) able to call several types of search engines, in particular relational search and text search, and perform set operations on the results from these different engines; - a cache memory (CR, Figure 5) which gathers the questions already asked to the system as well as their respective answers, so that the questions already formulated can be answered more quickly when they appear in a new form, produced in particular by the aforementioned query engine; - a postprocessing tool (GEN_REP, Figure 5); an architecture proposing tools for connecting external applications, in particular visual interfaces, tools used to produce and maintain the data of the information system 1.

  As a result, equipped with these tools, the heterogeneous database query system of the invention is intended to interface in an intranet allowing a company, or a group of companies, to realize all necessary management operations on all the heterogeneous data files contained in the data deposit box Similarly, the heterogeneous data interrogation system 3o of the invention is intended to be interfaced with the outside world by the through the Internet through the management of one or more websites.

  The data storage module 2 provides several advantages to the system of the invention.

  - Each group of copied data retains its structure defined by its own original data conceptual model without having to constrain it to a single model as is the case in other heterogeneous data management systems .

  - All data is in data box 2 without loss of information.

  The structure identity between the production system which established the data set 1 and the interrogation system 4 constituted by the interrogation system of the invention facilitates the understanding of the structure.

  Data maintenance is facilitated since the specialists of the different production systems recognize the conceptual model of their own data in the data box 2 thus allowing maintenance or updating for example by means of the power system.

  In one embodiment, the data storage module 2 also constitutes a data access portal insofar as the data can be grouped real or virtual. Depending on the needs, one can either copy the data, or keep them in the production system to view and extract at the time of the query.

  In another embodiment, the data organization module 3 also constitutes a data access portal insofar as it contains the connectivity resources associated with the domains (92, Figure 6) (93; which provide organized access to the searchable data by the system of the invention. A web client is then arranged to activate the connectivity resources 3o so that the data associated with each domain directly queried, for example using an interface IG1 (Figure 1) by the administrator Ad or another equivalent user , can be presented on a display console.

  As has already been exploded, the repository of data in the data repository module 2 (Figure 1) is not a mandatory measure. However, the choice of copying the data present in the production system or making a data repository has various advantages or disadvantages which are as follows.

  - When the data is copied physically in a part of physical copy (REC_PHY; Figure 5), one can gain in performances and avoid the overload of the system of production. This avoids annoying the users of the dataset 1 in their daily work. The overloads of the teleinformatic network of data production systems 1 are reduced because the queries go through the system of the invention and therefore this task is no longer predominantly affected. It is also possible to query database management systems that are not well suited to complex queries, such as document management systems. Finally, since the production systems are naturally permanently modified, data transformations can be performed during the power supply or within the data set 1.

  - When the data of the production systems are directly accessed without any copy, thanks to the copy of pointers as hypertext links in a virtual copy space of the data repository unit 2 (REC_VIR, Figure 5), they are accessible in real time which allows an economy of the storage space in the data storage unit 2, a saving in the duration of the supply of the database 2 and a limitation of the work time planning loads and bandwidth on the teleinformatic network that connects the data set 1 to the system of the invention.

  The heterogeneous database interrogation system of the invention comprises, in a particular embodiment, means allowing the user to choose between: optimizing the performance in the queries; and - promote access to information in real time; according to objectives that the user assigns when formulating a request and or setting up an interrogation session. Note that in this solution, the data is grouped either physically (REC_PHY; Figure 5) or virtually (REC_VIR), but always keeping their initial design scheme or model.

  The heterogeneous database interrogation system of the invention then comprises a means of supply (M_RECOPY; FIG. 5) of the data storage unit or module 2 which can be implemented by means of a scheduler (FIG. PLAN_REC; Figure 5) at regular intervals, for example every day or every week, as follows.

  The coded data maintained in the data set 1 and coming from software applications (not shown) that produce coded databases, such as a Lotus Notes application, are copied using a migration tool. encoded data to different relational database management systems, whether in physical form (in REC_PHY) or virtual form (in REC_VIR).

  - Static text data is copied from a web server thanks to an integrated web robot by means of M_RECOPIE copying (Figure 5) of the data repository module 2 - Data strongly structured and which are intended to be repeated in several types of databases, for example generic data on patients (sex, address, date of birth, date of eventual death, ...) are grouped on a generic data server (identity and movement server ) which is its own system for querying relational databases, which are not copied physically in REC_PHY (Figure 5), but are accessible directly, by registration in the virtual copy part REC_VIR (Figure 5) to take advantage of the time real, especially at the level of updates; - Documentary resources are copied from websites, using an intranet resource or an Internet resource (parts of M_RECOPIE) by making use of the aforementioned web robot.

  The data repository module 2 is based on a relational database query system such as a mySQL system which has the advantage of being widely used while retaining a high degree of performance and reliability.

  FIG. 5 shows elements making it possible to describe the operation of the interrogation system of the invention during two different modes of operation: a first mode of supplying the data storage module 2 with fresh data; a second mode of exploitation of the data deposited in the data storage module 2 by using the processing unit 4.

  Periodically, according to a periodicity determined preferentially by a copying planner PLAN_REC associated with the deposition module 2, the data storage unit 2 is connected to the data set 1 by a teleinformatic network not shown in FIG. network comprises an intranet type network on the one hand and, where appropriate, a network for accessing remote web resources on an Internet network, on the other hand. The basic or original data are stored in databases formed in data set 1.

  In the first mode or power mode, the original data is copied using a data copying means M_RECOPIE. According to the status of the recorded data 1, a status determined by a not shown configuration means, the copy means M_RECOPIE copies the data or physically in the form of a physical copy in a physical copy memory REC_PHY, or in the form of pointers where hypertext links in a recopy area REC_VIR. The operation of copying, or supplying, or depositing data exploits a plurality of computing resources that are described elsewhere.

  In the second mode or operating mode, an unrepresented user activates a GEN_FORM form generator which activates a metamotor MM described elsewhere which then activates the data storage module 2. Moreover, depending on the type of data interrogated, the form generator GEN_FORM interrogates the virtual copy space REC_VIR and / or the physical copy space REC_PHY of the data storage module 2 as well as a request cache cache CR which contains the previous stored searches. A request form is transmitted via the structuring unit 3 which will be described elsewhere so that, if the physical data is required, they are forwarded directly to a GEN_REP response generator of the processing unit 4 If the requested data are in the virtual copy area REC_VIR, the data storage module 2 produces a connection to the set of data 1 or to a website determined by the pointer addressed in the virtual copy memory REC_VIR and the recovered data are then routed, via the data organization module 3, directly from the data set 1 to the GEN_REP response generator of the processing unit 4. The response to the request produced by the forms generator GEN_FORM is then compiled with the previous responses obtained and stored in the CR request cache, and the final response is made accessible to the user using the GEN_REP response generator in the form of a display screen, a web page, or a printed representation as known in the state of the art.

  We will now briefly describe an embodiment of the data organization module 3. The purpose of such a unit is to make it easy to find the information and, for this purpose, the organization module 3 makes it possible to carry out the following operations.

  The organization module 3 comprises means for organizing and means for storing the data contained in the data deposit module 2 or directly in the data set 1.

  io - The organization module 3 includes a search engine for executing queries on all the data whatever their type, whether texts, structured data or not.

  - The organization module 3 also comprises a means for generating visual interfaces intended to allow the user to formulate requests and exploit their response.

  Finally, the organization module 3 comprises a tool for creating links between the data and external applications, in particular statistical tools or other navigation or data post-processing systems.

  The data organization means or structuring unit 3 comprises a means for generating, over the pre-existing data structure, a top organization layer. Such an organization layer is of object type, and it is structurally separated from the underlying relational layer. To generate such an object layer, the means for creating the organization layer comprises means for performing the grouping of one or more query domain query tables as well as a means for creating multiple links between the query domains. and their grouping into entities called metadomains.

  A query domain is a logical data grouping entity corresponding to one or more tables arranged in the memories REC_PHY and REC_VIR of the data storage module 2. The means for generating a query domain comprises means for grouping data, the explicit realization of its data and a means to annotate the data. Thus a domain includes, in addition to the data itself, metadata describing the nature of the information: - not explicit,

- description,

  - type of data, io - date of validity, etc. A domain administrator operates a RL2-connected computer (Figure 1) to the ad-type network of the Ad administrator (Figure 1). Such an administrator assists the users connected to the teleinformatic network for the definition of the domains an IGI visual interface of administration to help to classify and generate the domains according to the recommendations of the users. A domain administration means, which can be managed by the domain administrator includes: - a means for defining the domains, - a means for realizing the domain layout, - means for defining and managing a plurality of domains. organizational entities including: * domains and object types that a domain has 25 (connectivity resources, visualization, model, primary key): * metadomains; * metamodels; * elements of forms.

  In a preferred embodiment, the domain creation assistance generator comprises a means for realizing a grouping of data and domains, grouping identical to that of the production systems. This approach has several advantages.

  - The user finds the information from his own production system with an identical layout.

  - The user benefits from the reflection made during the design of the production system on the grouping of data.

  - Data has a different meaning to the limit semantics depending on their source, depending on the specified domain. For example in oncology, the term necrosis does not mean the same thing depending on whether it is used in clinical, pathology or radiology. It follows that the term necrosis orients the search according to the domain that has been specified to establish the query.

  An advantage of the present invention is to make possible the creation of domains while the relational database management systems are heterogeneous, local or remote in the set of data 1. The data organization module 3 comprises means to relate data invariably present in the original set of data 1 or in the data storage module 2.

  The data organization module 3 also comprises a metadomain management means. A metadomain within the meaning of the invention is an object that makes it possible to connect entities that are in the data storage module 2, which has the same semantics while originating from different data production systems. These entities, which can come from various database fields, are destined to end up in different query domains. To be associated in a metadomain, the data entities used to compose a metadomain are corelated beyond their relocation or their heterogeneous origin.

  To realize the metadomain management means, the latter comprises a first means for identifying common entities and for declaring in the data deposit module 2 or in the data set 1 as a semantic entity intended to receive a message. corelation. The first common entity identification means comprises a common entity input means and a means for declaring a corelation between several common entities entered in memory means provided for this purpose in the data storage module 2 by the common entity input means.

  The metadomain management means then comprises a second means for identifying individually in each of the domains, which would have been designated in the domain management means, the entity having the semantics defining the corelation regardless of its assigned name or the data typing. .

  In the case of the application of the interrogation system of the invention to a treatment of the records of various patients treated in a hospital, it is considered that each patient is identified by a unique file number. The different database production systems have tables, each of which has a column containing the feature entity of the unique folder number. To obtain a corelation of the data recorded in the various databases, such as clinical data and, radiology images, tumors stored in the tumor library as well as data from the identity server and movements, it is possible to use or to build a corelation, because all this data concerns the same patient or the same list of patients. However, the entity that stores the unique file number has a different name in each of the data production systems. For example, in a first database query system, the file number entity can be labeled NumDossier while in a second database query system, the same entity can be labeled N_Doss. The problem is multiplying with more than two database management systems. In addition, their data typing is rarely identical and can be an integer, a string of characters or a string of characters of defined length, ... and is thus copied into the data storage module 2 in forms heterogeneous inaccessible in a unified way. Moreover, depending on whether certain data are physically copied into the physical copy memory or virtually into the virtual copy memory, their access does not take the same mode.

  To solve such problems, the second means of the metadomain management means makes it possible to individually identify the domains concerned by the same semantics. In this case, the second means of individual domain identification makes it possible to declare a semantic unit: here the patient and then to declare the key enabling the identification of a patient: the file number.

  Then, when the interrogation system of the invention allows to work in interrogation mode as has been described elsewhere. The second metadomain management means traverses the various domains already defined to find the corresponding entities, in this case NumDossier, N_Doss, ... and they are declared to have the same semantics as the newly defined metacle. The patient semantic unit thus groups together several domains managed by the structuring unit 4 on the criterion selected from the file number.

  The data organization module 3 also comprises a metaclean management means that makes it possible, in particular, to make metadomains by grouping together several query domains. In the above example, the metacle is constituted by N_Doss while the metadomain is constituted by patient. The concept of metacle used by the present invention obeys a number of rules which are now described.

  - The metaclete takes into account all the relational tables concerned by the corelation with which it is associated and it is not necessary that its field name is identical nor that its typing of data is the same.

  In a particular embodiment, the metadomains are produced on the basis of the Perl DBI interface of the public domain and can group relational tables of heterogeneous relational database management systems, such as Oracle, Access, etc. ( registered trademarks). In addition, the metaclean management means cooperates with a means for creating links.

  The metacle generated by the metaclean management means is a foreign key creating relationships between the local and remote data resources, by means of Intranet or Internet type connections.

  The metacle and its management means cooperate with a means of creating multiple relationships without physical modification of the data structure contained in the data storage module 2, while all this information is stored in the object layer, which is at - above the relational physical layer.

  As a result, the metadomain associated with a metacle generated by the metaclean management means of the invention is constituted as an object-oriented structure making it possible to create links between relational entities of the heterogeneous relational database interrogation system, installed on heterogeneous, remote or local platforms. The metadomain management means of the invention thus makes it possible to enrich the relational model by adding to it the benefits of the object model. The system of the invention, in a particular embodiment, therefore comprises a network construction means whose input is connected to the metadomain management means of the invention and the associated metaclean management means, to construct a complex network of relations and contexts between relational entities.

  We will now describe an application of the aforementioned concepts and their management means for a particular hospital information system. The hospital information system tracks the medical treatment of patients who have tumors and are hospitalized in care units. The users of the interrogation system of the invention, who are members of the nursing staff, exploit the aforementioned means to define different entities as metaclasses grouping the same data in several ways into various metadomains.

  Specification data or patient identification data make it possible to establish a metadomain characteristic of the patient, since many data relating to him can be related to each other, which has previously been described as a corelation. The tumor specification data of a patient makes it possible to establish a characteristic metadomain knowing that the patient may have several different tumors and that it is not always easy to link the successive elements or data to a tumor, especially when the patient presents several tumors, synchronous or successive. The characteristic data of a sample or biopsy on a patient makes it possible to generate a metadomain. Data describing hospitalization, taken as a particular episode of care, generates a new metadomain. More generally, descriptive data of an episode of care make it possible to generate a metadomain if one considers the phase of the diagnostic consultations, the phase of treatment, the consultations and acts coming within the framework of a surveillance, the assessment , then the treatment of a recurrence. The peculiarity of this metadomain is that its metacle is not an entity fed directly by the information system. But in such a case, the interrogation system of the invention comprises a means of calculating a relational entity defining a metadomain associated with a metacleic characteristic of a care episode. Such a metadomain management means is a means for managing virtual metadomains.

  Data characteristic of a phase of the disease, if we consider the following phases: - phase of local diseases, - phase of local recurrence, - phase of metastatic disease, - palliative phase, also allow to generate another metadomain.

  More generally, the interrogation system of the invention comprises means for managing different metadomains: a means for managing real metadomains: such a management means makes it possible to track and group the relations between entities concerning the patient, a biological sample or hospitalization.

  a means for managing virtual metadomains: such a management means cooperates with a calculating means, in particular a calculating means capable of consolidating data acquired successively over time according to sequences making it possible to standardize the digital data at the time; using a calculation operation according to programming criteria determined by the user of the interrogation system of the invention.

  For example, metadomaine hospitalization is defined by a hospitalization number, which serves as a metacle, to which one can attach: - administrative information: acts and mode of entry, hospital unit, etc. ; - statistical information on the patient: name, age, sex; - coded diagnostic medical information and acts for compatibility problems with social insurance management and compensation systems; - calculated information: length of stay, cost of stay, ...; - Textual information: at each stay, a report of hospitalization is written in free text, possibly in a structured way; - information on the production of an act and the consumption of medicines, transfusion, ...

  - information on the care administered, collected in a computerized care file, as contained in a microcircuit health card.

  We will now describe a particular embodiment of the structuring unit or data organization module 3 of the interrogation system shown in Figure 1.

  The embodiment described below uses software resources constituted by object classes which are divided into two categories: a first class of objects related to the structural organization of the data; a second class of objects associated with the creation of the visual interfaces.

  The first class of objects provides a way to generate a metamodel as it has been written elsewhere. In this particular embodiment, the metamodel is constituted by an EPI :: metamodel class object to refer to an object according to the semantics of the C ++ computer language or the Java computer language. Such a class object contains another object of class Tree :: DAG_Node which is an object available in libraries associated with the Java language and which are freely available to the public, the container of this public object inheriting all the basic functions to manage an acyclic directed graph. When creating a metamodel type object using the EPI :: metamodel class object of the invention, the vertex, nodes, and leaves of the metamodel represented by the generated acyclic directed graph simply contain the identifiers of the metamodel. metadomains or domains to which they refer.

  To make a metadomain, the means for generating a metamodel comprises means for managing metadomains and means for calling an object of classEPl :: MetaDomain that contains all metadata related to the realized metadomain, such as the explicit name of the metaclean.

  To perform a node metadomain, the means for generating a metamodel includes means for managing node metadomains and for calling an EPI :: Model class object that contains the data model, a particular data structure modeling the one-to-one relationship. between his own metacleas and that of the parent metadomains, as has been explained elsewhere.

  To realize a domain, the means for generating a metamodel comprises domain management means and for calling a plurality of class objects which are respectively: an object of class EPI :: Domain which contains all the metadata related to the domain, as for example the explicit names of all the fields, their typing, etc. ; an EPI :: DBase class object that provides connectivity with the relational database management systems to the relational table (s) to which the domain refers. In a particular embodiment, the class object concerned uses a DBI class object which is a public code that provides compatible connectivity with a number of relational database management systems such as Oracle, Sybase, an object EPI :: Model class which contains a 3o structure of particular data modeling the bijection between the primary keys and the metacommas of the parent metadomain; at least one object of class EPI :: Index :: * to interrogate fields in the data deposited in the copying unit 2 and that the SQL system can not interrogate efficiently and these class objects will be discussed further; an object of class EPI :: Form which comprises: - a means for automatically generating a visual interface allowing a user to formulate a query to interrogate the fields of the domain; - - means for analyzing the request made by the user and transcode into a language readable by a motor implemented in the interrogation unit 4; io - an object of class EPI :: DomainStats, which comprises: - - a means for generating statistics on the data of the domain; means for storing the generated statistics; - - means for managing a dictionary of statistics data generated and stored in the class object.

  We will now specify the objects of class EPI :: Index :: *. In a number of query situations, the relational table contains fields whose contents can not be effectively queried with a SQL type engine. To allow these fields to be polled, the EPI :: Index :: * class collection includes a means to create specialized indexes and ways to effectively query a non-queryable field using an SQL engine. A domain generated by the means for generating domains to include one or more objects of this type.

  Among the index class objects, EPI :: Index :: *, an EPI :: Index :: Regex class includes means for indexing, and for querying a field containing text using a Regex regular expression calculation language. In a particular embodiment, the means for interrogating a field containing text and contained in the class EPI :: Index :: Regex, cooperates with a cache memory system to support large load increases. As a result, by using the cache memory, the means for querying a text-containing field can search for sentences or textual motifs in relation in particular to the definition of one or more domains, as it has already been specified.

  The second class of objects provides a means for generating a visual interface as has been described elsewhere. The means for generating a visual interface of this particular embodiment comprises an object of class EPI :: Form which executes or implements means for generating a form of queries for querying a coherent set of data, structured by the unit. 3. To implement a means for generating a request form, the class object EPI :: Form includes means for calling or generating a plurality of form elements of a specific field of the generated domain. by an EPI :: FormElement class object that is responsible for querying and / or displaying a specific domain field. Objects in this class are not specific to a particular field, but to a particular data typing and query type or query class. As a result, EPI :: FormElement class objects are independent of the data. Each EPI :: FormElement class object includes: - a means to query one or more types of relational data (numeric types, date, text field, etc.); means for directly querying data in SQL language; means for querying the specialized indexes created by the query system for querying a field, for example a searchable textual index with the index class object EPI :: Index :: Regex; means for graphically representing a form element on a visual interface, such as a html page; means for interacting with the user filling in the form element in order to formulate his question, for example by using objects called in html tags inserted into an html page serving as a receptacle for the form; a means for analyzing the question represented by the user in the form of a html page and for generating the corresponding query in the engine language as well as a natural language.

  In Figure 7, there is shown a form of the interrogation system of the invention when operated by a user 5 (Figure 1). User 5 operates a visual interface from a computer station connected to the computer network of the interrogation system. The visual interface 100 addresses a form generator which is fed by a memory 105 of elements of forms which was previously composed on the one hand during the configuration of the interrogation system and on the other hand during a phase using the organization module 3, by the administrator Ad (Figure 1) on the basis of the model of the data retained by the administrator.

  The query composed using the form generator 101 is then addressed to the metamotor 102 as previously described and the composed request is addressed to a set of caches 84 and / or set of query engines 103 and The query is then exploited by the organization module 3 by its User part 105 so that the organization of the data in the form of a directed acyclic tree carried out by the user. organization into organization entities is then applied to the query in the form of traversing the nodes of the tree according to the bijective applications of descent of request going from the metadomains to the domains, then of reassembly of the answers going from the domains towards the metadomains until to provide a response in the form of a list of document references or other data units that are referenced either in the Repository Module 2 or in the repository game. The response is then made available both in the cache set 104 and at the visual interface 100.

Claims (19)

  1 - System for interrogating heterogeneous databases of the kind comprising: - a set (1) of databases, all or some of which may have their own interrogation system, - a means for generating an interaction between a user and a plurality of database set data, characterized in that the means for generating interaction between a user and a plurality of data of the database set (1) comprises: É A module (3) organizer data to associate them by reference to a plurality of organizational entities; A response data generation and interrogation module (4) which includes means for generating request forms and generating response data.   2 interrogation system according to claim 1, characterized in that it comprises a module (2) for depositing data and a connection means (6) to said data set (1) at least on dates of copying and in that the data storage module (2) comprises: - a relational database part (80); a portion of tree data (81).   3 - interrogation system according to claim 2, characterized in that the relational database part (80) of the deposition module (2) comprises means for interacting with a relational database query system of type SQL implemented in a module (84) belonging to the data organization unit (3).   4 - interrogation system according to claim 2, characterized in that the tree structured data portion (81) comprises means for interacting with a tree query system implemented in a module (85) belonging to the module ( 3) organization of the data.     An interrogation system according to any one of claims 2 to 4, characterized in that it has a plurality of computing resources capable of transferring the data from the original data set (1) to the filing unit of data (2), among which: a middleware application, which makes it possible to connect the document databases (70) to the relational part (80) of the data box (2) a middleware application, which makes it possible to connect the bases relational data (72) to the relational section (84) of the data box (2) a website import method (75) for transferring the web sites (74) to the relational portion (80) in the data box (2) a method of importing web sites into a tree structure in the tree part (81) of the data box (2); a method of importing tree data into the tree part (81) of the data box (2); a method for importing tree data (5) of the web type from the tree part (81) of the data box (2) to the relational part (80) of the data box (2); an import method (83) of textual tree data from the tree part (81) of the data box (2) to the relational part (80) of the data box (2).   An interrogation system according to claim 1, characterized in that the association by reference to a plurality of organization entities of the data organization module (3) is performed by a management means of at least one Data metamodel, consisting of metadomains, then query domains that are based on the form generator (11), in the form of a data structure based on a DAG-type acyclic directed tree.   7 interrogation system according to claim 6, characterized in that it comprises a metadomain management means.   8 interrogation system according to claim 7, characterized in that it comprises means for creating metamodels to prioritize the metadomains according to whether they are independent or dependent on other metadomains.   9 - interrogation system according to claim 8, characterized in that the means for creating metamodels io comprises resources and information necessary for interrogating a data source, among which: a connectivity resource (93) towards the data source; as a system for querying relational databases.   a pointing resource (95) on a predetermined model; a visual interface (94) allowing a user to formulate questions about the data.   An interrogation system according to claim 9, characterized in that it comprises means for generating domains comprising: a connectivity resource to the data source; - a set of metadata; - a visual interface of questions about the data associated with the domain.   11 - interrogation system according to one of claims 9 or 10, characterized in that it comprises a model management means for creating, updating, managing the components of a model so as to configure a one-to-one relationship which allows to point from a metadomain to a domain in a model.   12 - interrogation system according to any one of claims 9 to 11, characterized in that it comprises one or more tools among which: - a treatment unit shaped as a man-machine interface (4) having a visual interface type web, with query forms and tables presenting the results, as well as a query formulation module (GEN_FORM, Figure 5); - a query metamotcher (MM, Figure 5) able to call several types of search engines, including relational search and text search, and merge the results from these different engines.   a cache memory (CR, Figure 5) which gathers the questions already asked to the system as well as their respective answers, so that the questions already formulated can be compiled more quickly when they appear in a new form, produced in particular by the aforementioned query engine; a tool for post-processing the results (GEN_REP, Figure 5); - tools for connecting external applications.   13 interrogation system according to claim 12, characterized in that it comprises a means for interfacing in an intranet.   14 - interrogation system according to claim 12, characterized in that it comprises means for interfacing with the outside world through the Internet through the management of one or more websites.   15 - interrogation system according to claim 1 or 6, characterized in that the data organization module (3) comprises means for generating, on top of the pre-existing data structure (1 or 2), an upper layer organization, object type, structurally separated from the underlying relational layer.   16 - interrogation system according to claim 15, characterized in that the means for creating the organization layer comprises means for executing the grouping of several request domain query tables and means for creating links multiple between the query domains and their grouping into entities called metadomains.   17 - interrogation system according to claim 6, characterized in that it comprises a domain administration means, which comprises at least: a means for defining the domains, a means for realizing the domain arrangement, means for defining and managing a plurality of organization entities comprising: domains and the types of objects a domain comprises (connectivity resources, visualization, model, primary key): metadomains; * metamodels; * elements of forms.   18 - interrogation system according to claim 6, characterized in that the structuring unit (3) also comprises a metadomain management means which comprises a first means of identification of common entity and the declaration in the data storage unit (2) and / or the data set (1) as a semantic entity for receiving corelation.   19 - interrogation system according to claim 18, characterized in that the first common entity identification means comprises a common entity input means and a means of declaration of a corelation between several common entities entered in a memory means in the data deposit unit by the common entity input means.   An interrogation system according to claim 18, characterized in that the metadomain management means comprises a second means for identifying individually in each of the domains that would have been designated in the domain management means the entity having the semantics defining the corelation regardless of its assigned name or data typing.   21 interrogation system according to claim 20, characterized in that the second means of the metadomain management means makes it possible to individually identify the domains concerned by the same semantics by declaring a semantic unit, then its key.   22 - interrogation system according to claim 6, characterized in that the module (3) for organizing the data includes metaclés management means for making metadomains by grouping several domains of io queries.   23 - interrogation system according to claim 22, characterized in that each metacle and its management means cooperate with means for creating multiple relationships without physical modification of the structure of the data contained in the unit (2) for depositing data.   24 - interrogation system according to claim 22, characterized in that it comprises a network construction means whose input is connected to the metadomain management means and the associated metaclean management means, to build a complex network relationships and contexts between relational entities.     Query system according to any one of claims 6 to 24, characterized in that it comprises a calculation means of a relational entity defining a metadomain associated with a metaclean to constitute a virtual metadomain management means.   26 - interrogation system according to claim 25, characterized in that it comprises means for managing different metadomains: - a real metadomain management means for tracking and grouping relationships between entities; a virtual metadomain management means for cooperating with a calculation means, in particular a calculation means capable of consolidating data acquired successively in time according to sequences making it possible to standardize the digital data by means of an operation calculation according to user defined programming criteria.   27 - interrogation system according to any one of claims 6 to 26, characterized in that the data organization module (3) cooperates with software resources comprising: - a first class of objects of structural organization of the 10 data; a second class of objects for creating visual interfaces.   28 - interrogation system according to the preceding claim, characterized in that it comprises means for generating a metamodel on the basis of an EPI :: metamodel class object which contains another object of class Tree :: DAG_Node en inheriting all the basic features to manage an acyclic directed DAG graph.   29 - interrogation system according to the preceding claim, characterized in that the means for generating a metamodel comprises a metadomain management means and a means for calling an EPI :: MetaDomain class object which contains all the metadata linked to the metadomain carried out , as the explicit name of a metacle.   - Query system according to the preceding claim, characterized in that to achieve a node metadomain, the means for generating a metamodel comprises a node metadomain management means and to call an EPI :: Model class object which contains the data model, a particular data structure modeling the bijective relationship between its own metaclea and that of parent metadomains.   Inquiry system according to the preceding claim, characterized in that for realizing a domain, the means for generating a metamodel comprises domain management means and for calling at least one of a plurality of class objects comprising: an EPI :: Domain class object that contains domain-related metadata; an EPI :: DBase class object that provides connectivity with the relational database management systems and / or to the relational table (s) to which the domain refers; an EPI :: Model class object that contains a particular data structure modeling the bijection between the primary keys and the metachanes of the parent metadomain; at least one object of class EPI :: Index :: * for indexing fields in the data deposited in the data storage module (2) and / or the data set (1) for interrogation by a predetermined engine ; an object of class EPI :: Form which comprises: means for automatically generating a visual interface for formulating a query for querying the fields of the domain; means for analyzing the formulated request and transcribing it into a language readable by a motor implemented in the interrogation unit (4); an object of class EPI :: DomainStats, which comprises: - a means for generating statistics on the data of the domain; - - a means for storing the generated statistics; means for managing a dictionary of statistics data generated and stored in the class object.   Interrogation system according to the preceding claim, characterized in that to allow the interrogation of these fields, the collection of classes EPI :: Index :: * includes a means for creating specialized indexes and means for interrogating effectively a non-queryable field using an SQL engine.   Interrogation system according to the preceding claim, characterized in that it comprises an EPI :: Index :: Regex class which comprises means for indexing, and for interrogating a field containing text using a regular expressions calculation language. regex.   Inquiry system according to the preceding claim, characterized in that the means for interrogating a field containing text and contained in the class EPI :: Index :: Regex, cooperate with a cache memory system lo in particular to carry out searches for phrases or textual motives related in particular to the definition of one or more domains.     An interrogation system according to claim 26, characterized in that the means for generating a visual interface comprises an object of class EPI :: Form which executes or implements a means for generating a query form for querying a coherent set of data structured by the data organization module (3).   Inquiry system according to the preceding claim, characterized in that the EPI :: Form class object comprises means for calling or generating a plurality of form elements of a domain-specific field generated by a class object EPI :: FormElement to execute the query and / or display of a specific domain field.   An interrogation system according to the preceding claim, characterized in that each object of class EPI :: FormElement comprises: means for interrogating one or more types of relational data (numeric types, date, text field, etc.); means for directly querying data in SQL language; means for querying the specialized indexes created by the query system for querying a field, such as a searchable textual index with the index class object EPI :: Index :: Regex; means for graphically representing a form element on a visual interface, such as a page in html format; means for interacting with the user filling in the form element in order to formulate his question, for example by using objects called in html tags inserted into an html page serving as a receptacle for the form; io - a means for analyzing the question represented by the user in the form of a html page and for generating the corresponding sub-query in the engine language.   Method for interrogating heterogeneous databases to implement an interrogation system according to any one of the preceding claims, which is characterized by two main phases: a first phase of organization of the data by an administrator and executed based on at least one structure model of the data to be interrogated; a second phase of interrogation of the data by a user and executed on the basis of forms generated according to the organization of the data determined during said first phase of organizing the data.