Data base dynamic inquiry method and system

Abstract

The present invention provides a method for the dynamic database inquiry, including that the corresponding metadata is sought out among a plurality of preset metadata based on the specified information of users; The metadata consists of a description on the query field, a description on the filtering condition, a description on the ordering condition and a description on the query subobject; A query object is generated based on the acquired metadata information; Parameter interfaces are invoked to amend any item or any combined item of the query field, the filtering condition, the ordering condition and the query subobject according to actual demands; The information is amended according to the query object and the parameters of the query object, and SQL query sentences are generated; The SQL query sentences are carried out to accomplish the database query and return to the data result rowset. The present invention can achieve different queries, satisfy numerous and complicated query demands, lower the complexity of the application maintenance notably and boost the adaptability and the efficiency of the query mechanism by introducing filtering parameters during the operation.

Description

technical field [0001] The invention relates to the field of database applications, in particular to a method and system for dynamic database query. Background technique [0002] In many current software application systems (for example, J2EE enterprise applications, etc.), it is often necessary to combine the program and the database for use, that is, the problem of accessing the database is often faced, and database query is the most commonly used operation. Moreover, due to the complexity and variability of business in enterprise applications, database query is a very frequently used functional module, resulting in relatively high requirements for the performance, robustness, and scalability of the data query module. [0003] In the prior art, JDBC (Java Database Connectivity) API is generally used to implement the database query function module through programming. JDBC API is a specification for accessing databases in the Java language. A set of Java database programmi...

AI Technical Summary

Problems solved by technology

[0009] 1. Database view technology can only write logic according to SQL, without object-oriented programming interface, which is not conducive to user understanding, and cannot conveniently set condition parameters

[0010] 2. After the view definition is completed, it cannot be dynamically modified at runtime

And because many database query methods are often used in large-scale database applications, and the business is complex and changes with the expansion of the business, so many query statement definition and maintenance workloads are heavy; and no matter in the design period No matter how many query methods are defined, it is impossible to exhaustively define all future query methods. Therefore, if there are new changes in the external environment and the view cannot be dynamically modified, it will be difficult for the application to adapt to changes in query requirements.

[0011] 3. Views have poor adaptability, low work efficiency, and are not easy to maintain; general views need to query all the fields that may be used every time, which will double the amount of query data and low operating efficiency; on the contrary, if only querying specific scenarios Fields are not very versatile, and views need to be designed for each scenario, resulting in a substantial increase in maintenance workload

When the relationship between data tables in the system changes, or the query requirements change, all related views need to be modified, and the probability of error is high

[0012] 4. Views are shared across the application layer, and session-level isolation cannot be achieved, which may lead to mutual influence between sessions

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