Query statement processing method and device, equipment, medium and product

Abstract

The invention provides a query statement processing method and device, equipment, a medium and a product, after a database obtains a query statement of query meta-information, if a queried data object is stored in the database in a distributed storage mode, the query statement is stored in the database according to a mapping rule of the data object; the query statement is routed to the at least one database node storing the data object, and the query statement is executed to query the meta-information from the at least one database node, so that the database can still execute the query statement of the meta-information when storing the data in a distributed manner, and the query efficiency of the meta-information is improved. Therefore, the meta-information can be queried from at least one database node, and the effective processing of the database on the query statement and the accuracy of the query result are ensured.

Description

Technical Field

[0001] This application relates to the field of database technology, and in particular, to a method, apparatus, device, medium, and product for processing query statements. Background Art

[0002] The distributed cluster of a database is a technology that extends the database system to multiple database nodes. The database can divide the data into multiple parts according to specific rules and store multiple parts through multiple database nodes respectively to improve the availability and scalability of the database system.

[0003] In the prior art, when each database node stores part of the data in a distributed storage manner, it will establish and store the meta-information of this part of the data. When the database obtains a query statement for querying the meta-information, it is impossible to directly execute the query statement to query the meta-information of each database node.

[0004] Therefore, how to enable the database to execute a query statement for querying the meta-information of distributedly stored data to query the meta-information from database nodes is a technical problem to be solved in this field. Summary of the Invention

[0005] This application provides a method, apparatus, device, medium, and product for processing query statements, enabling the database to execute a query statement for meta-information when storing data distributively, so as to be able to query the meta-information from at least one database node storing the data object.

[0006] The first aspect of this application provides a method for processing query statements, including: obtaining a query statement for querying meta-information; when the data object queried by the query statement is stored in a distributed storage manner in the database, routing the query statement to at least one database node storing the data object according to the mapping rule for storing the data object; and executing the query statement to query the meta-information from the at least one database node.

[0007] In an embodiment of the first aspect of this application, routing the query statement to at least one database node storing the meta-information includes: when the query statement is used to query all the meta-information of the data object, routing the query statement to at least one database node storing the meta-information.

[0008] After executing the modified query statement, the method further includes: rewriting the physical name of the meta-information of the queried data object into a logical name according to the mapping rule for storing the data object; and / or, performing deduplication processing on the meta-information of the queried data object.

[0009] In one embodiment of the first aspect of the present application, routing the query statement to at least one database node storing the meta information includes: when the query statement is used to query the meta information of a specific target of the data object, and the data object is a sharded table or a global table, routing the query statement to any one of the database nodes storing the meta information; when the table object is a sharded table and the physical name of the data object in the at least one database node is inconsistent with the logical name of the data object, rewriting the logical name of the data object in the query statement as the physical name of the data object.

[0010] In one embodiment of the first aspect of the present application, routing the query statement to at least one database node storing the meta information includes: when the query statement is used to query the meta information of a specific target of the data object, and the table object is a single table, routing the query statement to the database node storing the single table.

[0011] After obtaining the query statement for querying the meta information of the query data object in one embodiment of the first aspect of the present application, it further includes: performing semantic analysis on the query statement to determine the data object queried by the query statement; or determining the data object queried by the query statement through the system table queried by the query statement.

[0012] The second aspect of the present application provides a processing device for query statements, including: an acquisition module for acquiring a query statement for querying meta information; a routing module for routing the query statement to at least one database node storing the data object according to the mapping rule for storing the data object when the data object queried by the query statement is stored in a distributed storage manner in the database; and an execution module for executing the query statement to query the meta information from the at least one database node.

[0013] The third aspect of the present application provides an electronic device, including: a memory and a processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, causing the processor to execute the method according to any one of the first aspects of the present application.

[0014] The fourth aspect of the present application provides a computer-readable storage medium storing computer-executable instructions, and when the computer-executable instructions are executed, the method according to any one of the first aspects of the present application is implemented.

[0015] The fifth aspect of the present application provides a computer program product including a computer program, and when the computer program is executed, the method according to any one of the first aspects of the present application is implemented.

[0016] The method, apparatus, device, medium, and product for processing query statements provided by this application, when the database obtains a query statement for querying meta-information, if the data object to be queried is stored in a distributed storage manner in the database, then according to the mapping rule of the data object, the query statement is routed to at least one database node storing the data object, and the query statement is executed to query the meta-information from at least one database node, so that the database can still execute the query statement for meta-information when storing data distributively, and further can query the meta-information from at least one database node, ensuring the effective processing of the query statement by the database and the accuracy of the query result. Brief Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a schematic diagram of the application scenario of this application;

[0019] Figure 2 It is a schematic flowchart of an embodiment of the method for processing query statements provided by this application;

[0020] Figure 3 It is a schematic flowchart of an embodiment of the method for processing query statements provided by this application;

[0021] Figure 4 It is a schematic flowchart of an embodiment of the method for processing query statements provided by this application;

[0022] Figure 5 It is a schematic structural diagram of a query statement processing device provided by this application;

[0023] Figure 6 It is a schematic structural diagram of an electronic device provided by this application. Detailed Description of the Embodiments

[0024] The following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the drawings in the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.

[0025] The terms "first", "second", "third", "fourth", etc. (if any) in the description, claims and the above-mentioned drawings of the present application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily limit to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0026] Before formally introducing the embodiments of the present application, some technical terms involved are first explained.

[0027] Database sharding: The data of a table is horizontally split into multiple shards according to a certain partitioning rule, and the data of each shard is stored on different physical databases. This operation is called database sharding.

[0028] Table sharding: The data that falls on a database instance after database sharding is further split into multiple shards according to a certain rule. This operation is called table sharding.

[0029] Single table: A table that does not specify a sharding rule and only falls on a single database node.

[0030] Sharded table: A table that specifies a sharding rule. The table is sharded by database and table according to the sharding rule, and each node has different data replicas.

[0031] Global table: It has the same replicas on each database node, that is, the table structure and data are the same.

[0032] Logical name: The name used when a user creates an object.

[0033] Physical name: It refers to the name used when storing in an actual database node.

[0034] The present application is specifically applied to a database. Among them, the distributed cluster of the database is a technology that extends the database system to multiple database nodes. For example, Figure 1 is a schematic diagram of the application scenario of the present application, as Figure 1 shown, the database includes multiple database nodes, denoted as database node 1, database node 2... database node N, N is a positive integer, and the distributed database management system is used to manage multiple database nodes.

[0035] In a specific implementation manner, when the data object processed by the database is a table object, the distributed database management system can perform horizontal sharding on the table and store different shards on different database nodes, thereby horizontally expanding data storage to improve the availability and scalability of the database system. For example, the distributed database management system performs horizontal sharding on the table test to be stored, dividing it into four parts: table test0, test1, test2, and test3, and storing them in database node 1, database node 2, database node 3, and database node 4 respectively. According to different sharding rules, tables can be divided into three types: single tables, sharded tables, and global tables. When there is a single table, not all table information is contained in a single database node. Secondly, after the table is sharded, there may be a mapping rewrite from the logical name to the physical name, resulting in the problem of inconsistent physical and logical names.

[0036] For each data block node, when storing part of the data in a distributed storage manner, it will establish and store the metadata of this part of the data, so that each database node does not have the metadata of all data objects. When the distributed database management system of the database obtains a query statement for querying metadata, it cannot guarantee that directly routing the query statement randomly to a certain node can obtain the correct metadata, that is, it cannot guarantee the accuracy of the result.

[0037] In addition, when executing a query statement, there are also technical problems that if there are multiple shards of a table on the data source, the name of the sharded table is returned, and when querying specific table information, the physical name must be used to query the metadata, and the logical name cannot be used to query.

[0038] Based on the above problems, the present application provides a method, device, equipment, medium, and product for processing query statements, enabling the database to effectively execute query statements for metadata when storing data distributedly, so as to be able to query metadata from at least one database node storing data objects.

[0039] The technical solution of the present application will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0040] Figure 2 It is a flowchart of an embodiment of the method for processing query statements provided by the present application. As Figure 2 shown, the method for processing query statements can be applied to Figure 1 the scenario shown and is executed by the distributed database management system. Specifically, as Figure 2 shown, the method for processing query statements includes:

[0041] S101: The distributed database management system obtains the query statement of the query meta-information.

[0042] S102: When the data object queried by the query statement obtained in S101 is stored in the database in a distributed storage manner, the distributed database management system routes the query statement to at least one database node storing the data object according to the mapping rule of the data object.

[0043] S103: The distributed database management system executes the query statement processed by S102 to query the meta-information from at least one database node.

[0044] In one embodiment, the distributed database management system can obtain the statement input by the user, and this statement can specifically be a Structured Query Language (SQL) statement.

[0045] In one embodiment, the query statement specifically queries the meta-information of the data object, where the data object can be a library object, a schema object, a table object, a view object, an index object, a function object, a stored procedure object, etc.

[0046] In one embodiment, after determining that the query statement is a statement for querying meta-information, the distributed database management system performs the subsequent processing in Figure 2 It can be understood that after determining that the query statement is not a statement for querying meta-information, the distributed database management system may not perform the subsequent processing in Figure 2 the subsequent processing.

[0047] In one embodiment, after the distributed database management system obtains the query statement, it determines the data object queried by the query statement by means of semantic analysis of the query statement. Or, after the distributed database management system obtains the query statement, it determines the data object queried by the query statement according to the system table queried by the query statement. Among them, for the meta-information in the library, each type of database provides a custom system table for storage. Special syntax can be used during query or a specific system table can be queried. It can be determined therefrom whether it is a statement for querying meta-information, and the object type queried can be determined according to the system table it queries, with relatively high accuracy and calculation efficiency.

[0048] Specifically, in the embodiment of the present application, when the distributed database management system determines the data object queried by the query statement, it needs to perform routing selection according to the object name. Taking the table object as an example, according to the different meta-information of the table object queried by the query statement, the query statement needs to be routed to different database nodes.

[0049] Among them, the specific processing method for different tables refers toFigure 3 , Figure 3 This is a flowchart of an embodiment of the method for processing query statements provided by this application, showing a specific implementation manner of routing query statements to different database nodes.

[0050] As Figure 3 shown, when the distributed database management system obtains a query statement and identifies that the query object is a table object, it determines whether the query statement queries the specific information of a certain table.

[0051] When the query statement is used to query the meta-information of the specific target of the data object, and the data object is a sharded table or a global table, the query statement is routed to any one of the database nodes storing the data object. Among them, when it is determined that the query statement queries the specific information of a certain table, such as the meta-information of a certain column, since the meta-information of this column is stored in each database node, therefore, routing the query statement to any one of at least one database node storing the data object can achieve the query of the meta-information. Exemplarily, the table test is divided into 4 parts: table test0, test1, test2, and test3, and are respectively stored in database node 1, database node 2, database node 3, and database node 4. When querying the meta-information of the columns of test, the query statement can be routed to any one of database node 1, database node 2, database node 3, and database node 4.

[0052] Furthermore, when it is determined that the data object is a sharded table, when the physical name of the data object in at least one database node is inconsistent with the logical name of the data object, the distributed database management system also rewrites the logical name of the data object in the query statement to the physical name. In one embodiment, the distributed database management system specifically defines the sharding rules and the selected routing node in the previous step to determine its physical name in the corresponding node, so as to modify the logical name to the physical name. When rewriting, it is necessary to rely on the defined sharding rules and the previously selected routing node to determine its physical name in the corresponding node. In one embodiment, the distributed database management system performs routing selection according to the object name. When the mapping rules for different objects are different, the distributed database management system processes each object according to different mapping rules. Among them, the mapping rule refers to a corresponding relationship or conversion rule for converting one representation form into another representation form. In a database environment, the mapping rule is usually used for the conversion between logical names and physical names. This application does not limit the mapping rule, which can be determined based on the naming convention of the database, system architecture requirements, or other business logics.

[0053] When the query statement is used to query the meta - information of the specific target of the data object, and the data object is a single table, route the query statement to the database node storing the single table. Among them, when it is determined that the query statement is querying the specific information of a single table, since the meta - information of the single table is only stored in the database node where the single table is stored, the query statement is thus routed to the database node storing the single table.

[0054] When the query statement is used to query all the meta - information of the data object, route the query statement to at least one of the database nodes storing the meta - information. Among them, when it is determined that the query statement is not querying the specific information of a certain table, but the meta - information of all tables, since there is no complete meta - information in each database node, full - database routing is required. Therefore, route the query statement to at least one of all the database nodes storing the data object. Exemplarily, divide the table test into 4 parts, namely table test0, test1, test2, and test3, and store them in database node 1, database node 2, database node 3, and database node 4 respectively. When querying the meta - information of test, the query statement needs to be routed to all database nodes 1, 2, 3, and 4 to query the 4 parts test0, test1, test2, and test3 respectively, so as to obtain the meta - information of all tables test0 - test4, and then obtain the meta - information of table test. Another example, when 4 single tables are respectively stored in database nodes 1, 2, 3, and 4, and a query statement is received to query the meta - information of all tables, after routing the query statement to all database nodes, query the meta - information of all single tables stored in database nodes 1, 2, 3, and 4, and aggregate the meta - information of the single tables obtained by the query, and then obtain the meta - information of all the tables being queried.

[0055] In one embodiment, after routing the query statement to at least one of all the database nodes storing the data object and the distributed database management system executes the query statement, rewrite the physical name of the meta - information of the queried data object to the logical name according to the mapping rule of the stored data object. Specifically, when there are objects with inconsistent logical names and physical names in the result set returned by executing the query statement, and the physical name is queried from the database, it needs to be mapped to the logical name and then returned to the client.

[0056] In one embodiment, when a query statement is routed to at least one database node storing data objects, after the distributed database management system executes the query statement, it also performs deduplication processing on the meta-information of the queried data objects. Specifically, for the case where the relationship between the logical object and the physical object is one-to-many, the query results may have duplicate results, and after deduplication, they need to be returned to the client that sent the query statement, so as to complete the query of the meta-information.

[0057] It can be understood that the above-mentioned rewriting of the physical name of the meta-information of the queried data object into a logical name and the deduplication processing of the meta-information of the queried data object can both be referred to as the merging of query results, and either one can be executed according to the specific situation, or both need to be executed.

[0058] In one embodiment, when the query statement is used to query the meta-information of the specific target of the data object, after the distributed database management system processes and executes the query statement, the returned result set can be directly returned to the client that sent the query statement, so as to complete the query of the meta-information.

[0059] In summary, for the query statement processing method provided by this application, when the database obtains a query statement for querying meta-information, if the queried data object is stored in a distributed storage manner in the database, according to the mapping rule of the data object, the query statement is routed to at least one database node storing the data object, and the query statement is executed to query the meta-information from at least one database node, so that the database can still execute the query statement for meta-information when storing data in a distributed manner, and further can query the meta-information from at least one database node, ensuring the effective processing of the query statement by the database and the accuracy of the query results obtained by executing the query statement.

[0060] Figure 4 This is a schematic flowchart of an embodiment of the query statement processing method provided by this application, as Figure 4 shown Figure 2 and Figure 3 provide a specific implementation manner of the query statement processing method. Specifically, as Figure 4In the method shown, after the distributed database management system receives the SQL from the user, it first needs to determine whether it is an SQL for querying meta-information. If so, it needs to identify the data objects to be queried from it, such as database objects, schema objects, table objects, view objects, index objects, function objects, stored procedure objects, etc. After confirming the specific data objects, it is necessary to perform routing selection according to the object names. Taking the table object as an example, if all table information is queried, since each node does not have complete information, full-database routing is required. If it is to query the column information of a certain table, for a sharded table or a global table, it is only necessary to select one database for routing. If it is a single table, it needs to be routed to the database where it is located. After confirming the routing node, for objects with inconsistent logical names and physical names, it is necessary to rewrite the values in the SQL to generate a statement that can be sent to the database. When rewriting, it is necessary to rely on the defined sharding rules and the routing node selected in the previous step to determine its physical name on the corresponding node, so as to modify the logical name to the physical name. When merging the result sets, for objects with inconsistent logical names and physical names, what is queried from the database is the physical name, which needs to be mapped to the logical name and then returned to the client. For the relationship between logical objects and physical objects that is one-to-many, the query results may have duplicate results, which need to be deduplicated and then returned to the client. Thus, when using a distributed cluster, due to the rewriting of table names and the different ways of table database partitioning, the problem that meta-information cannot be queried correctly on each data node is solved. Specifically, by querying all database nodes and then aggregating the meta-information, it is ensured that the query results of meta-information are the same as those in the single-machine case.

[0061] In the foregoing embodiments of the present application, the method for processing query statements provided by the embodiments of the present application has been introduced. In order to implement each step and function in the method for processing query statements provided by the embodiments of the present application, the distributed database management system as the execution subject can be implemented through a hardware structure and / or software module. For example, the above functions can be implemented in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. Whether a certain function among the above functions is executed in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module depends on the specific application and design constraints of the technical solution.

[0062] For example, Figure 5 is a schematic structural diagram of a query statement processing device provided by the present application. As Figure 5 shown, the device can be used to execute the query statement processing method provided in any embodiment of the present application. In one embodiment, as Figure 5The processing device 1000 for the query statement shown includes: an acquisition module 1001, a processing module 1002, and an execution module 1003. Among them, the acquisition module 1001 is used to acquire the query statement for querying meta-information; the processing module 1002 is used to route the query statement to at least one database node storing the data object according to the mapping rule for storing the data object when the data object queried by the query statement is stored in a distributed storage manner in the database; the execution module 1003 is used to execute the query statement to query the meta-information from the at least one database node.

[0063] For the specific implementation manner and principle of the above processing device for the query statement, refer to the description in the foregoing processing method for the query statement, which will not be elaborated here.

[0064] It should be noted that it should be understood that the division of each module of the above device is only a division of logical functions. In actual implementation, it can be fully or partially integrated into a physical entity, or physically separated. And these modules can all be implemented in the form of software called by a processing element; they can also all be implemented in the form of hardware; or some modules can be implemented in the form of software called by a processing element, and some modules can be implemented in the form of hardware. For example, the processing module can be a separately established processing element, or can be integrated in a certain chip of the above device. In addition, it can also be stored in the memory of the above device in the form of program code, and the function of the above determination module is called and executed by a certain processing element of the above device. The implementation of other modules is similar. In addition, all or part of these modules can be integrated together or can be independently implemented. The processing element mentioned here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules can be completed by the integrated logic circuit in hardware in the processor element or by instructions in software form.

[0065] For example, the above-mentioned modules can be one or more integrated circuits configured to implement the above methods, such as: one or more application specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs), etc. Again, when a certain module above is implemented in the form of a processing element scheduler code, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processors that can call program code. Again, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0066] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another, for example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that the computer can access, or a data storage device such as a server or data center that includes one or more integrated available media. The available media can be magnetic media (for example, floppy disks, hard disks, magnetic tapes), optical media (for example, DVDs), or semiconductor media (for example, solid state disks (SSDs)), etc.

[0067] For example, Figure 6 is a schematic structural diagram of an electronic device provided by the present application. As Figure 6 shown, the device can be used to execute the query statement processing method provided in any embodiment of the present application. In one embodiment, as Figure 6The electronic device 2000 shown includes one or more processors 2001 and a memory 2002; wherein, the memory 2002 is used to store computer-executable instructions, and the processor 2001 can execute the computer-executable instructions stored in the memory 2002. When the computer-executable instructions are executed by the processor 2001, the processor 2001 is caused to implement the processing method of any query statement in the foregoing embodiments of the present application. In one embodiment, as Figure 6 the electronic device 2000 shown further includes a communication interface 2003, wherein, the processor 2001 can communicate with other devices through the communication interface 2003, such as obtaining a query statement.

[0068] The present application also provides a computer-readable storage medium, which stores computer-executable instructions, and when the computer-executable instructions are executed, they can be used to implement the processing method of any query statement in the foregoing embodiments of the present application.

[0069] The embodiments of the present application also provide a chip for executing instructions, and the chip is used to execute the processing method of any query statement in the foregoing of the present application.

[0070] The embodiments of the present application also provide a computer program product, including a computer program, and when the computer program is executed, it implements the processing method of any query statement in the foregoing of the present application.

[0071] Those of ordinary skill in the art can understand that all or part of the steps of implementing the foregoing method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps including the foregoing method embodiments; and the foregoing storage medium includes: various media such as ROM, RAM, magnetic disk, or optical disc that can store program codes.

[0072] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for processing query statements, characterized in that, including: a query statement for obtaining query meta-information; when the data object queried by the query statement is stored in a distributed storage manner in the database, routing the query statement to at least one database node storing the data object according to the mapping rule for storing the data object; executing the query statement to query the meta-information from the at least one database node.

2. The method according to claim 1, wherein The routing the query statement to at least one database node storing the data object includes: when the query statement is used to query all the meta-information of the data object, routing the query statement to at least one database node storing the data object.

3. The method according to claim 2, characterized in that, After executing the modified query statement, it further includes: rewriting the physical name of the meta-information of the queried data object into a logical name according to the mapping rule for storing the data object; and / or, performing deduplication processing on the meta-information of the queried data object.

4. The method according to claim 1, characterized in that, The routing the query statement to at least one database node storing the data object includes: when the query statement is used to query the meta-information of a specific target of the data object, and the data object is a sharded table or a global table, routing the query statement to any one of the database nodes storing the meta-information; when the table object is a sharded table, and the physical name of the data object in the at least one database node is inconsistent with the logical name of the data object, rewriting the logical name of the data object in the query statement into the physical name of the data object.

5. The method according to claim 1, wherein The routing the query statement to at least one database node storing the data object includes: when the query statement is used to query the meta-information of a specific target of the data object, and the table object is a single table, routing the query statement to the database node storing the single table.

6. The method according to any one of claims 1-5, characterized in that, After obtaining the query statement for querying the meta-information of the query data object, it further includes: performing semantic analysis on the query statement to determine the data object queried by the query statement; or, determining the data object queried by the query statement through the system table queried by the query statement.

7. A processing device for query statements, characterized in that, including: an acquisition module for acquiring a query statement for querying meta-information; a processing module for routing the query statement to at least one database node storing the data object according to the mapping rule for storing the data object when the data object queried by the query statement is stored in a distributed storage manner in the database; an execution module for executing the query statement to query the meta-information from the at least one database node.

8. An electronic device, characterized in that, including: a memory and a processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, causing the processor to execute the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, storing computer-executable instructions, and when the computer-executable instructions are executed, implementing the method according to any one of claims 1-6.

10. A computer program product, characterized in that, including a computer program, and when the computer program is executed, implementing the method according to any one of claims 1-6.

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