CN1282111C - Across-platform data base researching method - Google Patents

Abstract

The present invention discloses a cross-platform database query method. The method comprises the steps that a query file of a uniform format is constructed; a user input query information in the query file; the user sends out a query request to a database processing unit in a file mode; the database processing unit allocates a database subprocessing unit to each query request; the database subprocessing unit constructs database SQL query statements according to the allocated query file; a database query is carried out; the database subprocessing unit processes a query result and returns a query result file to the user. The present invention shields the difference between different platforms and the network transmission bottleneck of large data quantity queries by using file transmission, uses a uniform file structure to reduces the complexity of the users, effectively enhances the mobility of the users, reduces the processing complexity of the users, enhancing the operating compatibility of different platforms and raises the access speed of database queries.

Description

A cross-platform database query method

technical field

The present invention relates to a database operation method, in particular to a database query method.

Background technique

For any cross-platform operating system, shielding the differences between operating platforms is a key component. For any system that needs to use database storage and access, the requirement for convenient and quick database access is also essential, especially when it involves database access with large data volume or extremely complex query conditions. A good database query should not require the user to care about the actual location of the database, and at the same time, when the user's query location changes, there is no need to modify any access interface, and the data in the database can still be accessed correctly, conveniently and quickly.

Most of the current cross-platform database queries use the network configuration methods and tools provided by the database, or connect to the database with ODBC or JDBC, and input query requirements and query requests for query. Such as the NET8 configuration and WORKSHEET tools provided by the ORACLE database. Using these methods, there are the following disadvantages: 1. Each query requires repeated input of query conditions; 2. When a large amount of data is requested, network transmission bottlenecks will occur; 3. Different users or users on different platforms The connection to the database needs to be reconfigured when moving; 4. The return methods of query results vary greatly, and users cannot handle them uniformly, which increases the complexity of users.

Contents of the invention

The purpose of the present invention is to overcome the current shortcomings of using network configuration and tools for cross-platform database query, and propose a method that can shield the differences between platforms, reduce the complexity of user query processing, and can solve large data volume query requests A cross-platform database query method for the network transmission bottleneck problem.

The core idea of the present invention is: define a kind of unified file structure, be used for storing user's query condition and query result, server-side database processing unit carries out query in database according to the query condition defined in file structure, and query result is stored in a unified file structure.

The technical scheme of the present invention is as follows: a cross-platform database query method, comprising the following steps:

(1) Construct the query file of unified format, described query file comprises information control area and information data area, and information control area is used for storing user's inquiry condition and user's own information, and information data area is used for the return result of storage inquiry;

(2) The user inputs query information in the query file;

(3) The user sends the query request to the database processing unit in the form of a file;

(4) The database processing unit allocates a database sub-processing unit for each query request, and the database sub-processing unit is a database connection available for calling;

(5) The database sub-processing unit constructs a database SQL query statement according to the distributed query file;

(6) Perform database query;

(7) The database word processing unit processes the query result and returns the query result file to the user.

The content of the information control area includes: whether it is a joint query, the name of the query table, the list of query fields, query conditions, the name of the generated file, and user identification information. The content of the information data area includes: data header, used to record the number of fields and records queried; data type description, used to record the field type and field length; data record, used to record the specific content obtained by the query.

Above-mentioned step (5) specifically comprises the following steps:

(1) The database sub-processing unit invokes the file structure according to the user identification information in the query request, obtains the file structure and the file name given by the user in the information control area, and opens the file in a read-write mode in the given directory, if the file If it exists, it will be overwritten, if it does not exist, a new file will be generated;

(2) The database sub-processing unit judges the correctness of the user input query information in the query request, if the user fills in the information incompletely, returns failure information to the user, otherwise executes the next step;

(3) The database sub-processing unit constructs a database SQL query statement according to the query information filled in by the user;

(4) The database sub-processing unit verifies whether the query statement is correct, and if not, returns failure information to the user, otherwise executes the next query.

Database query refers to passing query statements to the database at one time, and obtaining query results one by one. Processing query results means that the database sub-processing unit writes the query results into the information data area of the query result file in network byte order, and after the query is completed, the database sub-processing unit closes the query result file.

The method also includes providing a series of file access interfaces, the access interface is a layer encapsulated on the access interface of the file system itself, so that the user does not need to care about the structure and source of the file when accessing the file. The access interface includes file creation, file opening, file writing, file reading, file closing, file positioning, file moving, current position of file pointer and file deletion.

Compared with the existing cross-platform database query method, the present invention especially considers the impact of the user's movement relative to the database platform on the query, and the bottleneck of the large amount of data query on the network transmission. In most cases, it is generally necessary to reconfigure the connection to the database, or adjust the user's query conditions to reduce the amount of data in the query results. The invention utilizes the transmission of files to shield the differences between different platforms and the network transmission bottleneck of querying large amounts of data, and reduces the complexity of users by utilizing a unified file structure. Adopting this method: 1. Effectively improves the mobility of users; 2. Can solve the problem of network transmission speed for large data volume queries; 3. Reduces the processing complexity of users; 4. Users do not need to care about the configuration of the database, which improves Improve the compatibility of operations between platforms; 5. Reduce users' frequent input of database query conditions and improve the access speed of database queries.

Description of drawings

Fig. 1 is the main flow chart of the query method of the present invention.

Fig. 2 is a schematic diagram of the structure of the query file.

Fig. 3 is a detailed flowchart of the step of "constructing query SQL statement by the sub-processing unit" in Fig. 1 .

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Fig. 1 is the main flow chart of the query method of the present invention. As shown in FIG. 1 , the query method proposed by the present invention includes the following steps: 1. Construct a query file in a unified format. The query file includes an information control area and an information data area. The information control area is used to store the user's query conditions and the user's own information, and the information data area is used to store the returned result of the query. The structure of the query file is further described in the description of FIG. 2 . 2. The user inputs query information in the query file. The file structure is presented to the user as an initial template, and the user fills in the initial template according to his own query requirements, and the information filled in by the user is recorded in the information control area of the file structure. 3. The user sends the query request to the database processing unit in the form of a file. When the user confirms his filling, the completed file structure will be sent to the database processing unit for storage. During the operation of the system, the user can modify the query information at any time, and the modified query information will be recorded immediately and reserved for future use. middle. 4. The database processing unit allocates a database sub-processing unit for each query request, and the database sub-processing unit is a database connection that can be called. The user can send the query request to the server database processing unit for query, and the database processing unit schedules the query request and allocates an available database connection for each request. This individual database connection can be called a database sub-processing unit. The database processing unit schedules query requests, allocates them according to the idleness of each sub-processing unit, finds an unloaded database processing sub-unit, and allocates the request to this database processing sub-unit. 5. The database sub-processing unit constructs a database SQL query statement according to the allocated query file. The query of the database is mainly completed through a certain SQL query statement, and the detailed description of this step will be carried out in Figure 3. 6. Perform database query, pass the query statement into the database at one time, and obtain the query results one by one. 7. The database word processing unit processes the query result and returns the query result file to the user. The database sub-processing unit writes the query result into the information data area of the query result file in network byte order, and after the query is completed, the database sub-processing unit closes the query result file. The user's request for database query can be synchronous or asynchronous, depending on whether the user cares about the returned result immediately.

Fig. 2 is a schematic diagram of the structure of the query file. As shown in Fig. 2, the present invention defines a unified file structure, which can adapt to the query requirements of various users. Users can define the query information according to their own needs, which will be used as the basis for obtaining the following SQL statements and writing the query results. The query file with a unified structure includes an information control area and an information data area. The information control area is used to store the user's query conditions and the user's own information, and the information data area is used to store the returned results of the query. Definition of information control area Different systems may have different definitions, but the basic information is the same: the query information definition part of the information control area can define query objects, query conditions, etc.; the user information definition part of the information control area can define user identification information, such as:

Is it a joint query

query table name

Query field list (default is all fields in the table)

Query conditions (the default is all records)

generated filename

user identification information

The information data area of the file structure can generally be composed of the following parts:

The data header part of the information data area is used to record the number of fields and records to be queried;

The data type description part of the information data area is used to record the field type and field length, etc.;

The data record part of the information data area is used to record the specific results of the query;

Of course, different systems may have different definitions for the contents of the information control area and the information data area.

Fig. 3 is a detailed flowchart of the step of "constructing query SQL statement by the sub-processing unit" in Fig. 1 . As shown in Figure 3, it specifically includes the following steps: 1. The database sub-processing unit invokes the file structure according to the user identification information in the query request, obtains the file structure and the file name given by the user in the information control area, and in the given directory with Open this file in read-write mode, if the file already exists, overwrite it, if it does not exist, generate a new file; 2. The database sub-processing unit judges the correctness of the query information entered by the user in the query request, if the user fills in the information is incomplete , then return failure information to the user, otherwise execute the next step; 3. The database sub-processing unit constructs a database SQL query statement according to the query information filled in by the user; 4. The database sub-processing unit verifies whether the query statement is correct. The user returns a failure message, otherwise executes the next query. The user sends a query request to the database processing unit, and the database sub-processing unit analyzes the request and judges the correctness of the information entered by the user (such as verifying whether the table name is filled in, etc.). If the information is incomplete, it will return failure to the user. Otherwise, after receiving the query request assigned by the database processing unit, the database sub-processing unit first searches in the information control area to obtain relevant query information, and forms an SQL statement for query according to the obtained query information, and simply checks the statement Correctness (such as whether there is a table name in the verification statement, etc.) If the verification is correct, the next query is performed, otherwise, an error number is returned to the user. Once the database sub-processing unit verifies the correctness of the query statement, it will pass the query statement into the database, and execute the corresponding query operation in the database. The query statement is sent to the database at one time, and the query results are obtained one by one. In order to shield the differences between different platforms, the sub-processing unit conducts a preliminary analysis on the query results, and writes the query results into the information data area of the file in network byte order. When the query is complete, the database subprocessing unit closes the file and prepares to return to the user.

In order to facilitate the user's access to the query result file, this method provides a series of file access interfaces. These access interfaces use the access interface of the file system itself, and encapsulate a layer on the original interface. The encapsulation layer provides The analysis of query information and the judgment and processing of different platforms in the network make it unnecessary for users to care about the source and structure of files when accessing files. These access interfaces include file creation, file opening, file writing, file reading, file closing, file positioning, file moving, current position of the file pointer, and file deletion. A brief description of these access interfaces is as follows:

·File Creation

Determine whether the file exists, if it exists, determine whether it needs to be overwritten, and if so, overwrite the original file;

If the file does not exist, create it directly;

·File open

Determine how the file is opened, and open the file as required;

·File writing

Determine whether to write query information or query results, and write files according to different write requests;

·File reading

Judging whether to read the query information or the query result, the database processing subunit calls to read the query information, and the user calls to read the query result;

· File close

close the open file;

·File location

Locate the pointer of the file to a certain position;

·File movement

Move files from one place to another, either between the same platform or between different platforms;

·The current position of the file pointer

Return the current position of the file pointer;

·File deletion

Delete the file from somewhere, if there is no permission, return failure and tell no permission to delete, if there is permission, delete directly.

In a preferred embodiment of the present invention---telecom network management system (client/server mode), adopt method described in the present invention to realize to database inquiry, main implementation steps are as follows:

1. Definition of query conditions

According to the unified file structure provided in the above method, the information control area and the information data area are respectively defined, and part of the template structure of the information control area is defined as follows:

Information Control Area Header

Whether it is a joint query (can be defaulted, the default is a single table query)

generated filename

user identification information

Information Control Area Contents

query table name

Query field list (can be defaulted, the default is all fields)

Query conditions (can be defaulted, the default is all records)

The partial template structure of the information data area is defined as follows:

Data header: the number of fields and records for record query, etc.

Data type description: record field type and field length, the length of the entire structure is the number of fields

Data record: record the specific content obtained by query

The client fills in the initial template according to its own query requirements. When the client confirms its filling, the filled file structure is sent to the database processing unit for storage. During the operation of the system, the client can modify the query information at any time through the interface, and the modified query information will be recorded immediately and retained for future use.

2. Query request processing

The client sends the query request to the server database processing unit for query, the database processing unit schedules the query request, finds the database processing subunit without load, and assigns the request to the database processing subunit, when the database subprocessing unit receives When the query request arrives, call the file structure according to the user identification information, obtain the file name given by the user in the file structure information control area, and open the file in read-write mode in the given directory of the server. If the file already exists, overwrite it. Generates a new file if it does not exist.

The assigned sub-processing unit implements a specific query request, and stores the query result in the information data area of the file. When a query is completely completed, the sub-processing unit returns the file to the client. The client's request for database query can be synchronous or asynchronous, depending on whether it cares about the returned result immediately.

We provide a series of API functions to perform database operations. In order to enable as many database operations as possible to operate concurrently when the number of database connections is limited, for simple query operations, first put the query results into the result cache, and then fetch each result one by one when fetching data.

3. Query statement acquisition

After receiving the query request assigned by the database processing unit, the database sub-processing unit first searches in the information control area to obtain relevant query information, and forms an SQL statement for query according to the obtained query information, and simply checks the statement. Correctness (such as whether there is a table name in the verification statement, etc.) If the verification is correct, the next query is performed; otherwise, an error number is returned to the client.

4. Make an inquiry

Once the database sub-processing unit verifies the correctness of the query statement, it will pass the query statement into the database, and execute the corresponding query operation in the database.

The query statement is sent to the database at one time, and the query results are obtained one by one. In order to shield the differences between different platforms, the sub-processing unit conducts a preliminary analysis on the query results, and writes the query results into the information data area of the file in network byte order. When the query is complete, the database sub-processing unit closes the file and prepares to return to the client.

The query method proposed by the present invention is applicable to any client/server mode. Adopting the method proposed by the present invention makes it possible to complete the access of each module to the database under the limited number of database connections, shielding the access of each user module to the database; it also provides the monitoring function of the database at the same time, and solves the problem of mobile access to the database. The impact of queries, as well as the bottleneck problem of large data volume queries in network transmission, and reduce the complexity of query processing for users.

Claims (6)

1, a kind of platform database querying method is characterized in that comprising the following steps:

(1) inquiry file of structure consolidation form, described inquiry file comprises information Control district and information data district, and the information Control district is used to store user's querying condition and user's self information, and the information data district is used for the return results of storing queries;

(2) user's input inquiry information in inquiry file;

(3) user sends to database processing unit with query requests in the mode of file;

(4) database processing unit is the sub-processing unit of each query requests allocation database, and the sub-processing unit of described database connects for the database that can Gong call;

(5) the sub-processing unit of database is according to the inquiry file constructs database SQL query statement that distributes; Specifically comprise the following steps:

5.1 the sub-processing unit of database calls file structure according to the user totem information in the query requests, obtain file structure and the given filename of information Control district user, and under given catalogue, open this file with read-write mode, if this document exists, then cover, if there is no, then generate a new file;

5.2 the sub-processing unit of database is judged the correctness of user input query information in the query requests, if user's fill message is incomplete, then returns failure information to the user, otherwise carries out next step;

5.3 the Query Information that the sub-processing unit of database is filled in according to the user constructs the database SQL query statement;

5.4 whether the sub-processing unit checking of database query statement is correct, if incorrect, then returns failure information to the user, otherwise carries out next step inquiry;

(6) carry out data base querying, once import query statement into database, obtain Query Result one by one;

(7) database word processing cell processing Query Result and return the Query Result file to the user; Described processing Query Result is meant that the sub-processing unit of database writes the information data district of Query Result file with Query Result in the mode of network bytes preface, and after inquiry was finished, the sub-processing unit of database was closed the Query Result file.

2, platform database querying method according to claim 1 is characterized in that the content in described information Control district comprises: whether be conjunctive query, and inquiry table name, inquiry list of fields, querying condition, the filename of generation, user totem information.

3, platform database querying method according to claim 1 is characterized in that the content in described information data district comprises: data head, in order to the field number and the record number of record queries; Data type is described, in order to record field type and field length; Data recording, the particular content that obtains in order to record queries.

4, platform database querying method according to claim 1 is characterized in that the request of user to the data library inquiry, is synchronous or asynchronous request.

5, platform database querying method according to claim 1, it is characterized in that described method also comprises provides a series of file access interfaces, described access interface is to encapsulate one deck on the access interface of file system itself, makes the user need not to be concerned about the structure and the source of file when file is carried out access.

6, platform database querying method according to claim 5 is characterized in that described access interface comprises that document creation, File Open, file write, file reads, closing of a file, document alignment, file movement, file pointer current location and file delete.

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