Method and apparatus for reading data from database

Abstract

The embodiments of the present invention disclose a method and an apparatus for reading data from a database, which relate to databases, achieve the real-time update of caches, and reduce the complexity of overall application system development. The method of the present invention includes: according to the data contents which need to be cached by a cache node, a data read control table is established and a message queue is created for the data contents which need to be cached; when an application program updates the data in a database, a trigger corresponding to the data table of the update data writes the update data information of the data table and the identifier of the cache node into which the data table needs to be cached into the message queue corresponding to the data table; ; the cache node reads the message queue corresponding to the cache node according to the cache node identifier, and updates the data in the cache node according to the update data information. The embodiments of the present invention are mainly used in the process that the cache system reads data from a database and updates the cache.

Description

technical field [0001] The invention relates to the field of databases, in particular to a method and device for reading data from a database. Background technique [0002] In modern computer technology, the application of database is very extensive. It is a warehouse for organizing, storing and managing data. As the core of the entire application system, the importance of the database is self-evident. In most applications, database read operations are more intensive than write operations, and the query conditions are relatively complex. Most of the performance of the database is consumed in queries, especially in large-scale applications with high users and high concurrency. The cost of direct database read Very high, then the database will become the bottleneck of the entire application. A cache is a part of memory that is used to cache data. When the application needs the data, it can be fetched directly from the cache without accessing the database. Therefore, cachin...

AI Technical Summary

Problems solved by technology

This method has the following disadvantages: Each cache node needs to regularly poll the database when checking whether the data in the incremental table or the source table has changed. When the system is relatively large and there are many cache nodes, frequent and large polling of the database will It will seriously affect the performance of the database and put more pressure on the database, and the regular polling of each cache node must have a time interval. When the data of the incremental table or the source table changes, the real-time performance of updating the cache is not particularly high

However, this method needs to write corresponding cache update code for all functional modules that handle cache data updates

And because the changed data is transmitted through the application program, when multi-node caching is required in some large-scale application systems, because the data required by each caching node is different, it is necessary to configure each caching node accordingly, which will make the entire system It is very complex and cumbersome, and the development difficulty, development volume and maintenance volume will greatly increase

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