JP3016799B2 - Database query processing unit - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a database query processing device that receives a query to a database, and interprets, executes, and responds to the query as a series of processes.

(Prior Art) In an information processing apparatus, when an operator inputs an inquiry command from a terminal device, or when a certain program inputs an inquiry command stored on a magnetic disk, specific data in a certain database is In some cases, a direct search is performed and read or updated.

A device that inputs a database query command, directly executes a query, and immediately responds to the result of the query is referred to as a “database query processing device”.

FIG. 2 is a block diagram showing a configuration example of a conventional database query processing device.

In the figure, a database query processing device 120
Is a device that, when a database inquiry command is input from an input device 110 such as a terminal device, receives the database inquiry command and accesses the database 160. The database query processing device 120 is composed of a query analysis unit 130 including a query interpretation unit 131 and an object generation unit 132, an object conversion unit 140, and a database access unit 150.

Here, the query interpreting means 131 interprets the query in response to the database query command from the input device 110 and performs a syntax check. The object generator 132 generates an object from the query interpreted by the query interpreter 131. The object generation unit 140 converts the object generated by the object generation unit 132 into an executable object while referring to database definition information, data structure information, and the like. The data access means 150 is the object conversion means 1
Access the database 160 according to the executable objects from 40.

The input database query command and the configuration of objects generated from the command will be described using a relational database as an example. Here, the relational database is a database that can search and update a plurality of tabular data using various keys, and can identify a data set to be accessed by a table name or a column name. Things. As an example of this relational database, FIG. 3 shows table data called an employee management table. This table shows employee names,
It is composed of columns of employee number, age, and affiliation, and data of each employee corresponding to each column.

When searching a relational database of such a format, for example, the following inquiry command is input.

SELECT Name FROM Employee Management Table WHERE By inputting a query command with an age of <30 or more to the database query processing device 120 and executing the query command in the database query processing device 120, the employee whose age is less than 30 years old can be obtained. The member's name data is extracted.

Next, FIG. 4 shows a configuration of an object for relational database access.

The object 70 includes an object type 71 for identifying whether or not it is executable, access target column information 72 to be searched / updated, and a table for identifying tables and columns referred to in the inquiry. Identification information 73 and column identification information 74
, An inquiry condition 75, data conversion information 76 referred to for executing data conversion, and access path information 77 used for determining an access order of the table.

(Problem to be Solved by the Invention) In the conventional database query processing device 120, every time a query is received, the query is analyzed by the query analysis unit 130, and the object is converted by the object conversion unit 140, regardless of the query executed previously. Executing processing and accessing the database.

However, in such a database inquiry process, in many cases, a part of the immediately preceding inquiry is actually changed to execute the next inquiry.

For example, consider a case where the following database inquiry commands are sequentially executed on the employee management table described above.

Database query command 1 SELECT COUNT (*) FROM Employee management table WHERE Age <30 Database query command 2 SELECT Name FROM Employee management table WHERE Age <30 Database query command 1 is for employees under 30 years of age The database inquiry command 2 is an inquiry for knowing the names of employees whose ages are less than 30 years. The operator checks the number of data to be retrieved using the database inquiry command 1, determines the display mode and output destination of the corresponding data, executes the database inquiry command 2, and extracts actual data. And At this time, in the database query command 2, “FROM table name, WHERE age <30”
Although the contents are exactly the same as those of the database query command 1, the query analysis processing by the query analysis means 130 and the object conversion means 140
Performs the object conversion process.

In such a similar database query processing, even the same contents are repeatedly processed from the beginning, so that the query processing takes a long time and the response performance of the database query processing which requires a high responsiveness is improved. Is lowering.

Therefore, an object of the present invention is to provide a database query processing device having a high-speed database query processing capability.

(Means for Solving the Problems) The present invention provides a database query process in which a database query command is input from an input device, the query command is analyzed to generate an executable object, and the database is accessed using the executable object. In the apparatus, a query comparing means for inputting the database query command and comparing it with a previously executed query command, and as a result of the comparison by the query comparing means, the entire database query command is the previously executed query. If it is the same as the command, the already generated executable object is selected from the storage means described later. If the database query command and a part of the previously executed query command are the same, the same As a result of the comparison by the object comparison means and the query comparison means, which selects the object corresponding to the part from the storage means described later, all or part of the database query command that did not match is interpreted and grammatical errors and the like are interpreted. Query interpreting means for checking, and object generating means for generating an object from the query checked by the query interpreting means, or combining the object with the object selected by the object selecting means to generate a new object Object conversion means for converting an object generated by the object generation means into an executable object; a database query command; an object generated by the object generation means; A storage unit that associates and stores the executable object generated by the object conversion unit, and a database using the executable object selected by the object selection unit or the executable object generated by the object conversion unit. And a database access means for accessing.

(Operation) A database inquiry command is input to the inquiry comparison means from the input device. In the query comparison means, the previously executed database query command is compared with the database query command to be executed this time. As a result of the comparison, in the case of a similar or identical query (the case of a similar query refers to the case where the constituent parts (query parts) of the database query command match), the present invention has already generated the query. An object or an executable object can be used, and the query interpretation by the query interpretation unit and the object generation processing by the object generation unit can be omitted for these already generated objects and executable objects. In particular, as a result of the comparison by the inquiry comparison means, in the case of the same inquiry, the executable object can be extracted from the storage means in the object selection means,
The processing by the query interpreter, the object generator, and the object converter can be omitted. When generating (composing) an executable object required by the database access unit, an object (executable object) generated before is generated.
Can be used, so that the processing from receiving the inquiry to executing the inquiry to the database can be simplified. Therefore, high-speed database query processing can be performed, and thereby high processing response performance can be realized in database query processing.

(Example) Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a database query processing device according to the present invention.

In the figure, a database query processing device 20
A query analysis means 30 having a function of generating an object in consideration of a previously executed query, and an object conversion means 40 having a function of converting the object generated by the query analysis means 30 into an executable object. A storage unit 70 that manages the input database query command 11 and the object generated by the query analysis unit 30 in association with the executable object generated by the object conversion unit 40; and a storage unit 70 that manages the database 60 using the executable object. And a database access means 50 having a function of executing access.

Here, the query analysis means 30 is a query comparison means 31 for comparing the previously executed database query command with the current database query command.
An object selecting unit 32 for selecting an object that has already been generated based on the result of the comparison of the database query by the query comparing unit 31; a query interpreting unit 33 for interpreting the query and performing a syntax check; It comprises an object generating means 34 for generating an object from the query interpreted by the query interpreting means 33.

The query comparison means 31 corresponds to the previously executed database query command extracted from the query storage means 71 of the storage means 70 and the database query command 11 received from the input device 10 and the object shown in FIG. To compare. In this case, the inquiry comparison means 31 performs the above-described comparison for each corresponding part constituting the object shown in FIG. For example, in the following command example, corresponding to the object in FIG. 4, for example, "access column information section" indicating what to access (SELECT name in the following command example), and which table to access ( FROM Employee management table), and the “Query condition section”, which indicates under what conditions (WHERE age <30) the access condition section.

SELECT Name… Accessed column information section FROM Employee management table… Table identification information section WHERE Age <30… Query condition section The object selection means 32 is the result of the comparison by the query comparison means 31, and the entire database query command was previously executed. If it is the same as the query command, the executable object that has already been generated is selected from the executable object storage unit 73 of the storage unit 70, and this is supplied to the database access unit 60. If a part of the query command executed in the storage unit 70 is the same, the object corresponding to the same
This is to be selected and supplied to the object generating means 34.

The query interpreting means 33 is a query comparing means.
At 31, a syntax check is performed on all or part of the queries that are not equal as a result of the query comparison.

The object generating means 34 combines the object selected from the previous inquiry and the newly generated object stored in the object storing means 72 by the object selecting means 32 to generate an object corresponding to the current inquiry. I do.

The storage unit 70 includes an inquiry storage unit 71, an object storage unit 72, and an executable object storage unit 73, and stores the objects stored in the object storage unit 72 and the executable objects stored in the executable object storage unit 73. The object is the inquiry storage means 71
Is stored in association with the corresponding inquiry stored in the. Here, the query storage means 71 stores the syntax-checked query in the query interpretation means 33, and makes the query comparison means 31 usable in subsequent queries. In addition, the object generated by the object generating means 34 is stored in the object storage means 72 in association with the corresponding inquiry, and can be used by the object selecting means 32. The executable object storage means 73 stores the executable object generated by the executable object generation means 41 in association with a corresponding inquiry,
The use by the object selecting means 32 is enabled.

If the query comparing unit 31 interprets that all parts of the query are equal, the object selecting unit 32 executes the executable object corresponding to the query generated and stored by the executable object storage unit 73 during the previous query processing. Is supplied to the database access means 50 to access the database 60.

Further, the object conversion unit 40 converts the object received from the query analysis unit 30 into an executable format and generates an executable object. The executable object generated by the object conversion means 40 is stored in the executable object storage means 73 in association with the inquiry. The object conversion means 40 supplies the generated executable object to the database access means 50, and the database access means 50
To access.

Next, the operation of FIG. 1 will be described with reference to the flowchart of FIG. FIG. 5 is a flowchart of an inquiry process of the database inquiry processing device of FIG. Further, taking a relational database as an example of the database, for example, a database query command (a command such as SELECT name, FROM employee management table, WHERE age <30) as in the previous example is input device 1.
The case where the data is supplied to the database inquiry device 20 from 0 will be described.

First, the database inquiry command is input to the input device 10.
When input to the query analysis means 30 of the database query processing device 20, the query comparison means 31 compares each part constituting the database query command with previously executed query data stored in the query storage means 71. (Step S1). As a result of the comparison, if the entire query (the entire database query command) is equal to the previously executed query (the previously executed query command), the object selecting unit 32 returns the executable object storing unit 73 of the storing unit 70 The corresponding executable object is taken out and supplied to the database access means 50, and the database access means 50 accesses the database 60 (steps S2, S14, S15). If the result of the query comparison by the query comparing means 31 indicates that the entire database query (the entire database query command) is not equal to the previously executed query (the previously executed query command), the comparison result indicates that the object selection has not been performed. The object is passed to the means 32. In the object selecting means 32, based on the result of the comparison, for each of the access target column information section, the table identification information section, and the query condition section, if the corresponding object has a corresponding query, the corresponding object is determined. It is extracted from the object storage means 72 (steps S2 to S8). Here, the case where the command as in the previous example is used is taken as an example, so that the access target column information section, the table identification information section, and the query condition section in the object configuration in FIG. 4 may be compared respectively.
Thereafter, the query interpreting means 33 executes a syntax check of the query portion or the query as a result of the query comparison that are not equal (step S).
9) When it is confirmed that there is no grammatical error or the like, inquiry accumulation is performed to newly store the corresponding inquiry in the inquiry accumulation means 71 (step S10). Thereafter, in the object generating means 34, steps S4, S6,
The object fetched in S8 and the object for the new query portion generated here (the query portion that did not match by the query comparison means 31) are combined to generate (synthesize) the object for the current query (database If the part constituting the query command matches the part of the previously executed database query command) or create a new object for this query (the part of the database query command is the previously executed database query) When it does not match the component of the command at all) (step S11). Further, the object generated in step S11 is stored in the object storage unit 72 of the storage unit 70 in association with the inquiry (step S1).
2). Next, the object converting means 40 converts the object generated by the object generating means 34 into executable (generates an executable object) (step S13). Next, the database access unit 50 accesses the database 60 using the executable object generated by the object conversion unit 34 (Step S15).

As can be understood from the above description, the database comparison command executed previously and the database query command to be executed this time are compared by the query comparison means 31, and when the query is similar or the same (the similar query) Means that the constituent parts (query parts) of the database query command match.) In this case, the already generated objects and executable objects can be used. In other words, the query interpretation means 33 can omit the query interpretation and the object generation processing by the object generation means 34. In particular, if the result of the comparison by the query comparing means 31 is the same query, the corresponding executable object can be immediately extracted from the executable object storage means 73 of the storage means 70 in the object selecting means 32. The processing by the interpreter 33, the object generator 34, and the object converter 40 can be omitted.

As described above, it is possible to omit part or all of the query interpretation by the query interpretation unit 33 and the object (including executable object) generation processing by the object generation unit 34 and the object conversion unit 40.
In generating (composing) the executable object required by the database access unit 50, the previously generated object or the executable object can be used. However, when an executable object generated before is used, it becomes an executable object for database access as it is. Therefore, the processing from the time when the database inquiry processing device 20 receives the inquiry to the time when the inquiry to the database 60 is executed can be simplified as compared with the related art. Therefore, high-speed database query processing can be performed,
As a result, high processing response performance can be realized in the database inquiry processing.

The present invention is not limited to the present embodiment, and various applications and modifications can be considered without departing from the gist of the present invention. For example, in the present embodiment, as the storage means 70,
A memory such as a dynamic RAM is used. Therefore, the query storage unit 71, the object storage unit 72, and the executable object storage unit 73 that constitute the storage unit 70 may use separate memories, respectively. May be.

(Effect of the Invention) As described above, if the database query processing device according to the present invention is used, a previously executed database query command and a database query command to be executed this time are compared by query comparison means, and similar or identical database query commands are compared. In the case of an inquiry, it is possible to omit the query interpretation by the query interpretation unit and the object generation processing by the object generation unit for the already generated object or executable object. In particular, as a result of the comparison by the query comparing means, in the case of the same query, the executable object can be extracted from the storage means in the object selecting means, so that the processing by the query interpreting means, the object generating means and the object converting means is omitted. can do. Then, an executable object required by the database access unit is generated (configured).
In this case, the previously generated object and the executable object can be used, so that the processing from receiving the inquiry to executing the inquiry to the database can be simplified. Therefore,
High-speed database query processing can be performed, thereby achieving high processing response performance in database query processing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a database query processing device according to the present invention. FIG. 2 is a block diagram showing an example of a conventional database query processing device.
FIG. 4 is a diagram showing an example of the contents of a relational database, FIG. 4 is a diagram showing a configuration example of a database access object, and FIG. 5 is a flowchart of an inquiry process of the database inquiry processing device of FIG. 10 ... input device, 20 ... database query processing device, 30 ... query analysis means, 31 ... query comparison means, 32 ... object selection means, 33 ... query interpretation means, 34 ... object generation means, 40 …… Object conversion means, 50 …… Database access means, 60 …… Database.

Continuation of the front page (56) References JP-A-59-188766 (JP, A) JP-A-64-25238 (JP, A) JP-A-63-269224 (JP, A) JP-A-1-23428 (JP) , A) JP-A-1-118922 (JP, A) JP-A-1-23427 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06F 12/00 G06F 17/30

Claims (1)

(57) [Claims] 1. A database query processing device for inputting a database query command from an input device, analyzing the query command to generate an executable object, and accessing a database using the executable object, comprising: Inquiry comparison means for inputting and comparing this with a previously executed inquiry command, As a result of comparison by the inquiry comparison means, if the entire database inquiry command is the same as the previously executed inquiry command, An executable object that has already been generated is selected from storage means described later, and if a part of the database query command and the previously executed query command are the same, the object corresponding to the same part is selected. Object selecting means for selecting the following from the accumulating means; and query interpreting means for interpreting all or some queries of the database query command that did not match as a result of the comparison by the query comparing means and checking for grammatical errors and the like. Object generating means for generating an object from the checked query by the query interpreting means, or combining the object with the object selected by the object selecting means to generate a new object; Object conversion means for converting an object generated by the means into an executable object; a database query command; an object generated by the object generation means; Storage means for storing the executable objects associated with each other, and database access means for accessing a database using the executable objects selected by the object selection means or the executable objects generated by the object conversion means. And a database query processing device.