WO2024016594A1

WO2024016594A1 - Pseudo column implementation method and apparatus, electronic device, and storage medium

Info

Publication number: WO2024016594A1
Application number: PCT/CN2022/141533
Authority: WO
Inventors: 蒋伟; 唐钰杰; 苏飞; 周国剑; 曾令江
Original assignee: 天翼云科技有限公司
Priority date: 2022-07-19
Filing date: 2022-12-23
Publication date: 2024-01-25
Also published as: CN115292313A

Abstract

A pseudo column implementation method and apparatus, an electronic device, and a storage medium, relating to the field of cloud computing and big data platforms. The method comprises: receiving a query statement, the query statement being used for querying target data, and the query statement comprising a first statement and a second statement (S201); performing calculation on the first statement by means of an operator to obtain pseudo column information, and performing calculation on the second statement by means of the operator to obtain target data, an execution function for performing calculation on the first statement and an execution function for performing calculation on the second statement being stored in the operator (S202); and merging the pseudo column information and the target data to generate a tuple pseudo list (S203). According to the method, in the query process of implementing pseudo column information, no other additional calculation is performed, thereby reducing, to the maximum extent, the effect of calculation of pseudo column information on the performance of a system. The pseudo column information and the target data are combined into a tuple, thereby standardizing the implementation process of a plurality of pieces of pseudo column information.

Description

A pseudo-column implementation method, device, electronic equipment and storage medium

Technical field

This application relates to the field of cloud computing and big data platforms, and in particular to a pseudo-column implementation method, device, electronic equipment and storage medium.

Background technique

Oracle Database (Oracle) is a commercial database. Oracle is a closed-source database. You cannot add additional pseudo columns that your business needs in Oracle, and using Oracle will increase software costs. Relational database management system (Postgre Structured Query Language, PostgreSQL) is the world's most powerful open source relational database, with a strong academic atmosphere and a high degree of freedom. It is a free database software.

Currently PostgreSQL does not support Structured Query Language (Structured Query) for Oracle pseudo column information. Language, SQL) syntax, but PostgreSQL's open source agreement allows free modification of the source code to implement the SQL syntax of Oracle pseudo columns. There are multiple pseudo-column information in Oracle. If the pseudo-column only implements its own pseudo-column information during the adding process, in the subsequent source code development, adding other pseudo-column information or SQL functions will cause the language environment of the source code to become cluttered. , without logic, causing operational failure.

technical problem

How to make PostgreSQL compatible with Oracle pseudo-column SQL syntax to query pseudo-column information; and how to standardize multiple pseudo-column information is a question worthy of discussion.

Technical solutions

Embodiments of the present application provide a pseudo-column implementation method, device, electronic device, and storage medium for querying pseudo-column information and standardizing the implementation process of multiple pseudo-column information.

In the first aspect, embodiments of the present application provide a pseudo-column implementation method, including:

Receive a query statement, the query statement is used to query target data; the query statement includes a first statement and a second statement;

The operator calculates the first statement to obtain the pseudo column information, and the operator calculates the second statement to obtain the target data; the operator stores an execution function for calculating the first statement and a function for calculating the first statement. Calculate the execution function of the second statement;

The pseudo column information and the target data are combined to generate a pseudo list of tuples.

The above method does not add any additional calculations during the query process of pseudo-column information, thus minimizing the performance impact of computing pseudo-column information on the system. Merge pseudo-column information and target data into tuples to standardize the implementation process of multiple pseudo-column information.

Optionally, the method also includes:

The query statement includes a third statement; the third statement is used to define the projection specification of the tuple pseudo-list;

The third statement is calculated by the operator, and the pseudo-list of tuples is projected.

The above method achieves unified projection calculation by projecting the pseudo-list of tuples.

Optionally, the operator is used to calculate the first statement to obtain the pseudo column information, and the operator is used to calculate the second statement to obtain the target data, which specifically includes:

In the i-th calculation, the operator is used to calculate the first statement to obtain the i-th pseudo column information, and the operator is used to calculate the second statement to obtain the i-th target data;

Store the i-th pseudo column information and the i-th target data into the execution status structure included in the operator;

After the 1st calculation, obtain the 1st pseudo column information to the 1st pseudo column information, and the 1st target data to the 1st target data; the i is greater than or equal to 1 and less than or equal to 1 Integer; the I is an integer greater than or equal to 1.

The above method uses operators to calculate the first statement and the second statement, and the execution state structure stores the pseudo column information and target data, thereby minimizing the impact of calculation, statistics, and collection of pseudo column information on the performance of the system.

Optionally, merging the pseudo column information and the target data to generate a tuple pseudo list specifically includes:

Merge the first pseudo-column information to the I-th pseudo-column information to generate a pseudo-column element;

Merge the first target data to the I-th target data to generate target data elements;

The pseudo column element and the target data element are combined to obtain the tuple pseudo list.

The above method stores pseudo-column information and target data through tuple pseudo-lists, merges pseudo-column information and target data into tuples, and realizes unified management of pseudo-column information.

Optionally, the method also includes:

The tuple pseudo-list is stored in the tuple table slot management tuple included in the operator.

The above method realizes unified management of tuple pseudo-lists by managing tuples in tuple table slots.

In the second aspect, embodiments of the present application provide a pseudo-column implementation device, including:

A receiving module, configured to receive a query statement, which is used to query target data; the query statement includes a first statement and a second statement;

A calculation module, used to calculate the first statement through an operator to obtain pseudo-column information, and to calculate the second statement through the operator to obtain the target data; the operator stores the information used to calculate the first statement. The execution function and the execution function used to execute the second statement;

A processing module, configured to merge the pseudo column information and the target data to generate a pseudo list of tuples.

In an optional embodiment, the computing module is also used to:

In a third aspect, embodiments of the present application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, the processor implements the above Any pseudo-column implementation method in the first aspect.

In a fourth aspect, embodiments of the present application further provide a computer-readable storage medium. A computer program is stored in the computer-readable storage medium. When the computer program is executed by a processor, the pseudo-column implementation of the first aspect is realized. method.

In a fifth aspect, embodiments of the present application further provide a computer program product, including a computer program, which is executed by a processor to implement the pseudo-column implementation method in any one of the above-mentioned first aspects.

For the technical effects brought by any implementation method in the second to fifth aspects, please refer to the technical effects brought by the corresponding implementation method in the first aspect, which will not be described again here.

Description of drawings

Figure 1 is a schematic diagram of an application scenario of a pseudo-column implementation method provided by an embodiment of the present application;

Figure 2 is a flow chart of a pseudo-column implementation method provided by an embodiment of the present application;

Figure 3 is a schematic diagram of a query sentence input interface provided by an embodiment of the present application;

Figure 4 is a schematic diagram of pseudo column information and target data provided by an embodiment of the present application;

Figure 5 is a schematic diagram of another pseudo-column information and target data provided by an embodiment of the present application;

Figure 6 is a schematic diagram of a pseudo column element provided by an embodiment of the present application;

Figure 7 is a schematic diagram of a target data element provided by an embodiment of the present application;

Figure 8 is a representation of a tuple pseudo-column provided by an embodiment of the present application;

Figure 9 is a complete flow chart of a pseudo-column implementation provided by the embodiment of the present application;

Figure 10 is a schematic diagram of a device for pseudo-column implementation provided by an embodiment of the present application;

Figure 11 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

Embodiments of the invention

In the following, some terms used in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

1. The term "pseudo column" in the embodiment of this application is a database term, which means that this column does not exist physically and is only constructed during query. Pseudo columns are usually freely allocated and cannot be modified by users. For example, each row of data in an Oracle table has a unique identifier (RowID) field. You can use RowID to quickly locate a corresponding data, because it marks the physical address corresponding to the record, which is unique.

2. The term "tuple" in the embodiment of this application is a basic concept in a relational database. A relation is a table. Each row in the table (that is, each record in the database) is a tuple, and each column is an attribute. ;In a two-dimensional table, tuples are also called rows.

3. In the embodiments of this application, the term "SQL" means Structured Query Language (Structured Query Language) is a special-purpose programming language. It is a database query and programming language used to access data and query, update and manage relational database systems.

In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

The application scenarios described in the embodiments of the present application are for the purpose of more clearly explaining the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Persons of ordinary skill in the art will know that with the emergence of new application scenarios It appears that the technical solutions provided by the embodiments of this application are also applicable to similar technical problems. Among them, in the description of this application, unless otherwise stated, the meaning of "plurality" is two or more.

During the database source code development process, PostgreSQL does not support the SQL syntax of Oracle pseudo columns, but PostgreSQL's open source agreement allows you to freely modify the source code to implement the SQL syntax of Oracle pseudo columns and use it for production and commercial use. If multiple pseudo columns are added without corresponding specifications, subsequent program failures will occur. Therefore, it is necessary to implement the SQL syntax of Oracle pseudo columns in PostgreSQL, implement query of pseudo columns, and standardize the information of multiple pseudo columns.

In order to solve the above problem, embodiments of the present application provide a pseudo column implementation method, device, electronic device, and storage medium. For example, receive a query statement, which is used to query target data. The query statement includes a first statement and a second statement. The operator is used to calculate the first statement to obtain the pseudo column information, and the operator is used to calculate the second statement to obtain the target data. The operator stores an execution function for calculating the first statement and an execution function for executing the second statement. Merge pseudo column information and target data to generate a pseudo list of tuples. In this way, SQL syntax compatible with Oracle pseudo columns and customized pseudo column functions can be realized, the development of pseudo columns can be standardized, and the development efficiency of pseudo columns can be improved.

In the embodiment of this application, users can submit query statements through the client and query pseudo column information and target data on the server.

As shown in Figure 1, a schematic diagram of an application scenario of an optional pseudo-column implementation method in this embodiment of the application includes a server 100 and a terminal 101. The server 100 and the terminal 101 can achieve a communicable connection through the network, so as to Implement the pseudo column implementation method of this application.

The user can use the server 100 to interact with the terminal 101 through the network, such as receiving or sending messages. Various client applications can be installed on the terminal 101, such as programming applications, web browser applications, search applications, etc. The terminal 101 may be various electronic devices having a display screen and supporting web browsing, including but not limited to smart phones, tablet computers, desktop computers, and so on.

The client installed on the terminal 101 is used to respond to the query statement submitted by the user and send the query statement to the server, so that the server can query the pseudo column information and target data.

The server 100 is configured to receive a query statement, which is used to query target data; the query statement includes a first statement and a second statement. The operator is used to calculate the first statement to obtain the pseudo column information, and the operator is used to calculate the second statement to obtain the target data. The operator stores an execution function for calculating the first statement and an execution function for executing the second statement. Merge pseudo column information and target data to generate a pseudo list of tuples. The server 100 can be implemented as an independent server or a server cluster composed of multiple servers.

As shown in Figure 2, a flow chart of a pseudo-column implementation method provided by an embodiment of the present application may specifically include the following steps:

Step S201: Receive a query statement, which is used to query target data; the query statement includes a first statement and a second statement;

Step S202: Use the operator to calculate the first statement to obtain the pseudo column information, and use the operator to calculate the second statement to obtain the target data; the operator stores an execution function for calculating the first statement and an execution function for calculating the second statement. ;

Step S203: Merge the pseudo column information and the target data to generate a tuple pseudo list.

When the user needs to query the target data, the user can input the query statement through the client; the client sends the query statement submitted by the user to the server, and the server processes it.

In the implementation, when the target data needs to be queried, the user starts the client through the terminal's operation interface; for example, the user can double-click the client icon to start the client.

After the client is started, the query statement input interface is displayed in the client's display interface; as shown in Figure 3, the user can enter the query statement in this interface.

After the user enters the query statement in the interface, the user submits the query statement. Among them, the query statement is a statement written by SQL.

In step S201, the client receives the query statement submitted by the user, converts the query statement submitted by the user into a format according to the grammar parsing rules, and then provides the query statement for use by the operator.

In the embodiment of this application, the query statement submitted by the user includes a first statement and a second statement. The first statement in the query statement is used to query the pseudo column information; the second statement in the query statement is used to query the target data.

In step S202, in the i-th calculation, the operator is used to calculate the first statement to obtain the i-th pseudo column information, and the operator is used to calculate the second statement to obtain the i-th target data. Store the i-th pseudo column information and the i-th target data in the execution status structure included in the operator. After the 1st calculation, the 1st pseudo column information to the 1st pseudo column information, and the 1st target data to the 1st target data are obtained. Among them, i is an integer greater than or equal to 1 and less than or equal to I; I is an integer greater than or equal to 1.

In the running structure of PostgreSQL in the embodiment of this application, each operator includes an execution function, an execution status structure, and a tuple table slot management tuple. Among them, the execution function is used to calculate the query statement entered by the user. The execution status structure is used to save all the information from the 1st to the ith time when the execution function calculates the query statement. Tuple table slot management tuples are used to store tuple tables containing different information, including tuple pseudo-lists.

It should be noted that in the embodiment of this application, operators include top-level operators, projection operators and other operators. Different types of operators are called for calculation according to different query statements.

In the first calculation of the embodiment of this application, the first pseudo column information is obtained by calculating the first statement in the query statement submitted by the user through an operator. The first target data is obtained by calculating the second statement in the query statement submitted by the user through an operator. Save the first pseudo column information and the first target data in the execution status structure contained in the operator.

In the second calculation, the operator is used to calculate the first statement in the query statement submitted by the user to obtain the second pseudo column information. The second target data is obtained by calculating the second statement in the query statement submitted by the user through an operator. After the second calculation is completed, a row will be added to the tuple consisting of the pseudo-column information saved for the first time and the corresponding target data, and the second pseudo-column information and target data will be saved to the execution status structure contained in the operator. in the body.

In the i-th calculation, the operator is used to calculate the first statement in the query statement submitted by the user to obtain the i-th pseudo column information; the operator is used to calculate the second statement in the query statement submitted by the user to obtain the i-th target data. After the i-th calculation is completed, a row will be added to the tuple consisting of the pseudo-column information saved in the i-1 calculation and the corresponding target data, and the i-th pseudo-column information and target data will be saved to the tuple contained in the operator. in the execution status structure. Among them, i is an integer greater than or equal to 1 and less than or equal to I.

The embodiment of this application integrates the calculation process of collecting pseudo-column information into the operator calculation query statement, without adding other additional calculations, reducing the time for calculating pseudo-column information, and minimizing the impact of calculation and statistics of pseudo-column information on the system's performance. , this impact can be ignored in practical applications.

After all calculations corresponding to the query statement submitted by the user are completed, that is, after the Ith calculation. The field data corresponding to the pseudo-column information in different calculation times is collected through sources such as the statistical information stored in the execution status structure and the historical record information of the execution status structure. Among them, I is an integer greater than or equal to 1.

In an optional embodiment, the pseudo column information queried by the user may be an Oracle pseudo column (RowNum). In Oracle, RowNum returns the serialized numeric number of each row of data in the result set. ROWNUM is a sequence, which is the order in which Oracle reads data from the data file or buffer. The first record with a RowNum value is 1, the second record with a RowNum value is 2, and so on.

For example, the user enters a query statement on the client that wants to query integers greater than or equal to 2000, less than or equal to 2004, and RowNum information. The server receives the user's query statement and converts the query statement submitted by the user into a format according to the grammar parsing rules for calculation by the operator. After the first calculation of the operator is completed, as shown in Figure 4, the first pseudo column information is 1 and the first target data is 2000. The pseudo column information and target data are stored in the execution status structure contained in the operator. in the body. After the second calculation of the operator is completed, as shown in Figure 5, the second pseudo column information is 2 and the second target data is 2001. The second pseudo column information and target data are stored in the execution included in the operator. in the status structure. Until the fifth calculation is completed, all calculation times are completed. Collect the pseudo column information and target data in the fifth calculation process through the statistical information stored in the execution status structure. Collect all pseudo-column information and target data from the first calculation to the fourth calculation through the execution status structure history information.

In step S203, the first pseudo-column information to the I-th pseudo-column information are combined to generate a pseudo-column element. Merge the first target data to the I-th target data to generate target data elements. Merge the pseudo column elements and the target data elements to obtain a pseudo list of tuples.

In this embodiment of the present application, the first pseudo-column information to the I-th pseudo-column information are combined to generate pseudo-column elements. For example, in the pseudo-column element shown in Figure 6, the first pseudo-column information to the fifth pseudo-column information are: 1, 2, 3, 4, and 5 respectively.

Merge the first target data to the I-th target data to generate target data elements.

For example, as shown in Figure 7 for the target data elements, the first to fifth target data are: 2000, 2001, 2002, 2003, and 2004 respectively.

Merge the pseudo column elements and the target data elements to obtain a pseudo list of tuples.

For example, in the tuple pseudo-list shown in Figure 8, the pseudo-column elements are 1, 2, 3, 4, and 5, and the target data elements are 2000, 2001, 2002, 2003, and 2004. Merge the pseudo column element with the target data element.

After the tuple pseudo-list is obtained, the tuple pseudo-list is stored in the tuple table slot management tuple included in the operator, and the tuple pseudo-list is managed uniformly.

In this embodiment of the present application, pseudo column elements and target data elements are merged to obtain a tuple pseudo list. Tuple binding is used to prevent duplication of implementation during the implementation of pseudo-column information, or the query statement is calculated and run separately without obtaining the pseudo-column information and target data through tuples, resulting in obtaining the wrong pseudo-column. information and the condition of the target data.

In an optional embodiment, the tuple pseudo-list is projected accordingly according to the projection specification defined by the third statement in the query statement.

The embodiment of this application uses an operator to calculate the third statement and project the pseudo-list of tuples. Because the pseudo column information is the same before and after projection, the tuples are the same before and after projection. Therefore, only the target data can be projected according to the projection specification defined in the third statement. After projection, the query results with pseudo-column information are returned to the client, so that the user can obtain the query results with pseudo-column information.

For example, the pseudo column elements in the tuple pseudo list are 1, 2, and 3; the target data elements are -2000, -2001, and -2002. The projection specification defined in the third statement entered by the user is to find the absolute value of the target data; then the tuple pseudo-list is projected. Because the pseudo-column information is 1, 2, and 3 before projection, and the pseudo-column information is 1, 2, and 3 after projection, the pseudo-column information is unchanged. The tuple is 3 rows before projection and 3 rows after projection, the tuple is unchanged. So only the target data element is projected. After projection, the target data elements become 2000, 2001, and 2002, and the query results with pseudo column information are returned to the client.

In an optional embodiment, the pseudo-column information queried by the user may be an Oracle level (Level) pseudo-column. In the query of Oracle's Level pseudo column, Level represents the number of iterations of the operator. When the operator calculates the query statement, a mark field is defined in the operator to save the Level information. Hierarchical queries scan one level of nodes each iteration. Level is initialized to 1 when entering the initial node. For the initial value of Level, Level is incremented by 1 for each additional iteration.

When the query statement submitted by the user contains the first statement for searching for Level information, the data corresponding to the above marked field is returned to the user as pseudo column information. When the query statement submitted by the user does not contain the first statement used to search for Level information, the Level information will also be calculated, but will not be returned to the user.

For example, it receives a query statement and converts the query statement submitted by the user into a format according to the grammar parsing rules for use by the operator. The query statement includes a first statement for querying the Level pseudo-column, a second statement for querying the target data, and a third statement for defining the projection specification of the tuple pseudo-list. The operator is used to calculate the first statement to obtain the pseudo column information, and the operator is used to calculate the second statement to obtain the target data. Merge the first pseudo-column information to the I-th pseudo-column information to generate a pseudo-column element. Merge the first target data to the I-th target data to generate target data elements. Merge the pseudo column elements and the target data elements to obtain a pseudo list of tuples. Through the definition of the third statement, the tuple pseudo-list is projected; after the projection is completed, the query result with pseudo-column information is returned to the client, so that the user can obtain the query result with pseudo-column information.

In an optional embodiment, the query statement submitted by the user only needs the operator to be calculated once to obtain the pseudo column information and target data. The first pseudo column information is obtained by calculating the first statement in the query statement submitted by the user through an operator. The first target data is obtained by calculating the second statement in the query statement submitted by the user through an operator. Save the first pseudo column information and the first target data in the execution status structure contained in the operator. Merge the pseudo column information and target data to obtain a pseudo list of tuples. Through the definition of the third statement, the tuple pseudo-list is projected; after the projection is completed, the query result with pseudo-column information is returned to the client, so that the user can obtain the query result with pseudo-column information.

In the embodiment of this application, on the basis of PostgreSQL transmitting data through tuples, all pseudo-column information is added by merging the target data and pseudo-column information to generate a tuple pseudo-list, thereby standardizing the pseudo-column information development process. The operator calls the execution function to calculate the corresponding query statement, and uniformly calculates, collects and projects the pseudo column information, thereby uniformly managing the interface for obtaining query results. Implement SQL syntax compatible with Oracle pseudo columns and customized pseudo column functions to facilitate the continuous development of pseudo column functions.

As shown in Figure 9, this application provides a complete flow chart of pseudo column implementation.

Step S901: Receive a query statement, which includes a first statement, a second statement and a third statement;

Step S902. In the i-th calculation, the operator is used to calculate the first statement to obtain the i-th pseudo column information, and the operator is used to calculate the second statement to obtain the i-th target data; i is greater than or equal to 1;

Step S903: Store the i-th pseudo column information and the i-th target data into the execution status structure included in the operator;

Step S904: After the I-th calculation, obtain the first pseudo-column information to the I-th pseudo-column information, and the first to I-th target data; I is an integer greater than or equal to 1;

Step S905: Combine the first pseudo-column information to the I-th pseudo-column information to generate pseudo-column elements;

Step S906: Merge the first target data to the I-th target data to generate target data elements;

Step S907: Merge the pseudo column elements and the target data elements to obtain a tuple pseudo list;

Step S908: Store the tuple pseudo-list in the tuple table slot management tuple included in the operator;

Step S909: Calculate the third statement through the operator and project the tuple pseudo-list.

The embodiment of the present application provides a device for pseudo-column implementation, as shown in Figure 10. The device includes: a receiving module 1001, a computing module 1002, and a processing module 1003, wherein:

The receiving module 1001 is used to receive a query statement, the query statement is used to query target data; the query statement includes a first statement and a second statement;

The calculation module 1002 is used to calculate the first statement through an operator to obtain the pseudo column information, and calculate the second statement through the operator to obtain the target data; the operator stores information for calculating the first statement The execution function and the execution function used to execute the second statement;

The processing module 1003 is configured to merge the pseudo column information and the target data to generate a tuple pseudo list.

Optionally, the calculation module 1002 is also used to:

Optionally, in the source database, when the operator is used to calculate the first statement to obtain the pseudo column information, and the operator is used to calculate the second statement to obtain the target data, the processing module 1003 specifically Used for:

After the 1st calculation, obtain the 1st pseudo column information to the 1st pseudo column information, and the 1st target data to the 1th target data; the i is greater than or equal to 1 and less than or equal to 1 Integer; the I is an integer greater than or equal to 1.

Optionally, when the pseudo column information and the target data are merged to generate a pseudo list of tuples, the processing module 1003 is specifically used to:

Optionally, the processing module 1003 is also used to:

An embodiment of the present application also provides an electronic device. The electronic device 110 according to this embodiment of the present application is described below with reference to FIG. 11 . The electronic device 110 shown in FIG. 11 is only an example and should not impose any limitations on the functions and usage scope of the embodiments of the present application.

As shown in FIG. 11 , the electronic device 110 is embodied in the form of a general electronic device. The components of the electronic device 110 may include, but are not limited to: the above-mentioned at least one processor 111, the above-mentioned at least one memory 112, and a bus 113 connecting different system components (including the memory 112 and the processor 111).

Bus 113 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, a processor, or a local bus using any of a variety of bus structures.

Memory 112 may include readable media in the form of volatile memory, such as random access memory (RAM) 1121 and/or cache memory 1122 , and may further include read-only memory (ROM) 1123 .

The memory 112 may also include a program/utility 1125 having a set of (at least one) program modules 1124 including, but not limited to: an operating system, one or more application programs, other program modules, and program data. Each of the examples, or some combination thereof, may include the implementation of a network environment.

Electronic device 110 may also communicate with one or more external devices 114 (e.g., keyboard, pointing device, etc.), with one or more devices that enable a user to interact with electronic device 110 , and/or with one or more devices that enable the electronic device 110 110 Any device (such as a router, modem, etc.) that can communicate with one or more other electronic devices. This communication may occur through input/output (I/O) interface 115 . Furthermore, the electronic device 110 may also communicate with one or more networks (eg, a local area network (LAN), a wide area network (WAN), and/or a public network, such as the Internet) through the network adapter 116 . As shown, network adapter 116 communicates with other modules for electronic device 110 via bus 113 . It should be understood that, although not shown in the figures, other hardware and/or software modules may be used in conjunction with electronic device 110, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives And data backup storage system, etc.

In an exemplary embodiment, a computer-readable storage medium including instructions, such as a memory 112 including instructions, is also provided, and the instructions can be executed by the processor 111 to complete the above pseudo-column implementation method. Optionally, the storage medium may be a non-transitory computer-readable storage medium. For example, the non-transitory computer-readable storage medium may be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc. .

In an exemplary embodiment, a computer program product is also provided, including a computer program, which when executed by the processor 111 implements any of the pseudo-column implementation methods provided by this application.

In an exemplary embodiment, various aspects of a pseudo-column implementation method provided by this application can also be implemented in the form of a program product, which includes program code. When the program product is run on a computer device, the program code is used to The computer device is caused to execute the steps in the pseudo-column implementation method described above in this specification according to various exemplary embodiments of the present application.

The Program Product may take the form of one or more readable media in any combination. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may include, for example, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: electrical connection with one or more conductors, portable disk, hard disk, random access memory (RAM), read only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above.

The program product for the pseudo-column implementation method of the embodiment of the present application may adopt a portable compact disk read-only memory (CD-ROM) and include the program code, and may be run on an electronic device. However, the program product of the present application is not limited thereto. In this document, a readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, apparatus or device.

The readable signal medium may include a data signal propagated in baseband or as part of a carrier wave carrying readable program code therein. Such propagated data signals may take many forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A readable signal medium may also be any readable medium other than a readable storage medium that can send, propagate, or transport the program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a readable medium may be transmitted using any suitable medium, including but not limited to wireless, wireline, optical cable, RF, etc., or any suitable combination of the foregoing.

The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including object-oriented programming languages, such as Java, C++, etc., and also includes conventional procedural programming. language, such as "C" or a similar programming language. The program code may execute entirely on the user's electronic device, partly on the user's electronic device, as a stand-alone software package, partly on the user's electronic device and partly on a remote electronic device, or entirely on the remote electronic device or service Executed on the terminal. In situations involving remote electronic devices, the remote electronic devices may be connected to the user electronic device through any kind of network, such as a local area network (LAN) or a wide area network (WAN), or may be connected to an external electronic device, such as provided by an Internet service Business comes via Internet connection.

It should be noted that although several units or sub-units of the device are mentioned in the above detailed description, this division is only exemplary and not mandatory. In fact, according to embodiments of the present application, the features and functions of two or more units described above may be embodied in one unit. Conversely, the features and functions of a unit described above may be further divided into embodiments of a plurality of units.

Furthermore, although the operations of the methods of the present application are depicted in a particular order in the drawings, this does not require or imply that the operations must be performed in that particular order, or that all of the illustrated operations must be performed to achieve desired results. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step for execution, and/or one step may be broken down into multiple steps for execution.

Those skilled in the art will understand that embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable image scaling device to produce a machine such that the instructions executed by the processor of the computer or other programmable image scaling device generate a A device for realizing the functions specified in a process or processes in a flowchart and/or a block or blocks in a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable image scaling device to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means, the instructions The device implements the functions specified in a process or processes in the flowchart and/or in a block or blocks in the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable image scaling device, causing a series of operating steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

Although the preferred embodiments of the present application have been described, those skilled in the art will be able to make additional changes and modifications to these embodiments once the basic inventive concepts are understood. Therefore, it is intended that the appended claims be construed to include the preferred embodiments and all changes and modifications that fall within the scope of this application.

Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. In this way, if these modifications and variations of the present application fall within the scope of the claims of the present application and equivalent technologies, the present application is also intended to include these modifications and variations.

Claims

A pseudo column implementation method, characterized in that the method includes:

Receive a query statement, the query statement is used to query target data; the query statement includes a first statement and a second statement;

The operator calculates the first statement to obtain the pseudo column information, and the operator calculates the second statement to obtain the target data; the operator stores an execution function for calculating the first statement and a function for calculating the first statement. Calculate the execution function of the second statement;

The pseudo column information and the target data are combined to generate a pseudo list of tuples.
The method of claim 1, further comprising:

The query statement includes a third statement; the third statement is used to define the projection specification of the tuple pseudo-list;

The third statement is calculated by the operator, and the pseudo-list of tuples is projected.
The method according to claim 1 or 2, characterized in that: calculating the first statement through an operator to obtain pseudo column information, and calculating the second statement through the operator to obtain the target data, specifically include:

In the i-th calculation, the operator is used to calculate the first statement to obtain the i-th pseudo column information, and the operator is used to calculate the second statement to obtain the i-th target data;

Store the i-th pseudo column information and the i-th target data into the execution status structure included in the operator;

After the 1st calculation, obtain the 1st pseudo column information to the 1st pseudo column information, and the 1st target data to the 1th target data; the i is greater than or equal to 1 and less than or equal to 1 Integer; the I is an integer greater than or equal to 1.
The method according to claim 3, characterized in that merging the pseudo column information and the target data to generate a tuple pseudo list specifically includes:

Merge the first pseudo-column information to the I-th pseudo-column information to generate a pseudo-column element;

Merge the first target data to the I-th target data to generate target data elements;

The pseudo column element and the target data element are combined to obtain the tuple pseudo list.
The method according to claim 1, 2 or 4, characterized in that the method further includes:

The tuple pseudo-list is stored in the tuple table slot management tuple included in the operator.
A pseudo-column implementation device, characterized by including:

A receiving module, configured to receive a query statement, which is used to query target data; the query statement includes a first statement and a second statement;

A calculation module, used to calculate the first statement through an operator to obtain pseudo-column information, and to calculate the second statement through the operator to obtain the target data; the operator stores the information used to calculate the first statement. The execution function and the execution function used to execute the second statement;

A processing module, configured to merge the pseudo column information and the target data to generate a pseudo list of tuples.
The device according to claim 6, characterized in that the computing module is also used to:

The query statement includes a third statement; the third statement is used to define the projection specification of the tuple pseudo-list;

The third statement is calculated by the operator, and the pseudo-list of tuples is projected.
An electronic device, including a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that when the processor executes the computer program, any one of claims 1-5 is implemented The database migration method described.
A computer-readable storage medium on which a computer program is stored, characterized in that when the computer program is executed by a processor, the steps of the method according to any one of claims 1-5 are implemented.
A computer program product, characterized in that, when called by a computer, the computer program product causes the computer to execute the steps of the method according to any one of claims 1-5.