Method for accessing relational databases of different types

Abstract

The invention relates to a method for accessing relational databases of different types, comprising the following steps: encapsulating aiming at difference by analyzing and identifying the differenceof the relational databases of different types and editions; externally providing a consistent programming access interface in an assembly way, uniformly transferring a standard and a writing form foran SQL statement syntax and various database functions and commands and shielding the difference caused by the relational databases of different types and editions; internally respectively and pointedly realizing the shielding of the difference according to the types and the editions of the databases, and when the difference of the types and the editions of the databases is shielded, using two methods, i.e. the programming access interface and the SQL statement syntax, to encapsulate the difference. The two methods can be used together, therefore not only the effect on shielding the difference of the types and the editions of the databases can be achieved but also the complexity of realizing programming can be lower; meanwhile, the invention is lighter and has obvious advantages on execution efficiency corresponding to a way of using a complete private SQL statement syntax to define, analyze and translate the SQL statement syntax.

Description

Technical field

[0001] The invention relates to the field of relational databases, and in particular to a method for an application program to access a plurality of different types and versions of relational databases in an indiscriminate manner. Background technique

[0002] At present, relational database storage is the mainstream way of enterprise storage and data application. Popular large-scale relational databases include Oracle, SQL Server, IBM DB2, SyBase, Informix, etc., and each database generally has multiple parallel versions in use ( For example, Oracle 9i, Oracle 10g). Many relational database types follow or support consistent SQL language standards (such as ANSI / ISO SQL99, SQL92). However, various databases have extended some non-standard SQL based on this standard, and the data type definitions of various databases are not uniform. For the realization of the same functions, the functions and system commands provided by various databases are inconsistent. Even t...

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