[ https://issues.apache.org/jira/browse/SPARK-45449?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Wenchen Fan resolved SPARK-45449. --------------------------------- Fix Version/s: 3.5.1 4.0.0 Resolution: Fixed Issue resolved by pull request 43258 [https://github.com/apache/spark/pull/43258] > Cache Invalidation Issue with JDBC Table > ---------------------------------------- > > Key: SPARK-45449 > URL: https://issues.apache.org/jira/browse/SPARK-45449 > Project: Spark > Issue Type: Bug > Components: SQL > Affects Versions: 3.5.0 > Reporter: liangyongyuan > Priority: Major > Labels: pull-request-available > Fix For: 3.5.1, 4.0.0 > > > We have identified a cache invalidation issue when caching JDBC tables in > Spark SQL. The cached table is unexpectedly invalidated when queried, leading > to a re-read from the JDBC table instead of retrieving data from the cache. > Example SQL: > {code:java} > CACHE TABLE cache_t SELECT * FROM mysql.test.test1; > SELECT * FROM cache_t; > {code} > Expected Behavior: > The expectation is that querying the cached table (cache_t) should retrieve > the result from the cache without re-evaluating the execution plan. > Actual Behavior: > However, the cache is invalidated, and the content is re-read from the JDBC > table. > Root Cause: > The issue lies in the 'CacheData' class, where the comparison involves > 'JDBCTable.' The 'JDBCTable' is a case class: > {code:java} > case class JDBCTable(ident: Identifier, schema: StructType, jdbcOptions: > JDBCOptions) > {code} > The comparison of non-case class components, such as 'jdbcOptions,' involves > pointer comparison. This leads to unnecessary cache invalidation. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org