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Jspxcms itself does not do special caching. JPA is used in the system, and all caches are handled by JPA. So the cache here is actually the cache of JPA. For more information, check out the caching section of the JPA or Hibernate documentation.

JPA cache is divided into three parts: first-level cache, second-level cache and query cache.

First-level caching is an inherent function of JPA, that is, during a session cycle, the objects in it will be put into the cache. The first-level cache caches only individual objects. In a session cycle, querying the same object multiple times will only read the database once, and then all from the cache. This cache is turned on by default and cannot be turned off.

Secondary cache is a cache shared in multiple session cycles, such as objects queried in one session cycle, and the same object is queried in the next session cycle, which will be read from the cache instead of querying the database. In addition to individual objects, collections of one to many can also be placed in a secondary cache.

The query cache caches the results of sql statements.

What does the session cycle mean? The session here is JPA's session, not http's session. Using JPA generally turns on Open Session In View, that is, a http request is a session cycle.

In JPA, secondary caching and query caching are off by default. These two caches are opened in Jspxcms, configuration file: / WEB-INF/classes/conf/spring.jpa.properties

# second-level cache spring.jpa.properties.hibernate.cache.use_second_level_cache=true# query cache spring.jpa.properties.hibernate.cache.use_query_cache=true

Caching is critical for a system like cms that needs to deal with a lot of access. However, because of the existence of the cache, directly modify the database data manually, the data on the page will not change, you need to restart Tomcat to read the changed data. If caching must be turned off for some reason, you can set both caches to false, but system performance degrades.

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