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From Apache Wiki <wikidi...@apache.org>
Subject [Db-derby Wiki] Update of "StatementCache" by BryanPendleton
Date Mon, 21 Sep 2009 16:20:06 GMT
Dear Wiki user,

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The "StatementCache" page has been changed by BryanPendleton:
http://wiki.apache.org/db-derby/StatementCache?action=diff&rev1=1&rev2=2

  Derby caches prepared statements instances on a per-connection basis in the statement cache,
to avoid the overhead of re-preparing the statements.
+ 
+ The statement cache can be disabled by setting {{{derby.language.statementCacheSize=0}}},
though this parameter is not currently documented ([[https://issues.apache.org/jira/browse/DERBY-4280|DERBY-4280]]).
  
  Some code to look at while studying the statement cache includes:
  
- * GenericLanguageConnectionFactory.getStatementCache
+  * {{{GenericLanguageConnectionFactory.getStatementCache}}}
- * GenericLanguageConnectionContext.lookupStatement
+  * {{{GenericLanguageConnectionContext.lookupStatement}}}
- * GenericStatement.prepMinion
+  * {{{GenericStatement.prepMinion}}}
- * ConcurrentCache.find
+  * {{{ConcurrentCache.find}}}
- * GenericStatement.equals and GenericStatement.hashCode
+  * {{{GenericStatement.equals}}} and {{{GenericStatement.hashCode}}}
  
- There are some problems involved in using the statement cache. For one thing, sometimes
the statement cache causes us to fail to re-compile a statement when we *should* recompile
it (for example, if we were to recompile it now, we'd get a better query plan) -- DERBY-3892.
+ There are some problems involved in using the statement cache. For one thing, sometimes
the statement cache causes us to fail to re-compile a statement when we *should* recompile
it (for example, if we were to recompile it now, we'd get a better query plan) -- [[https://issues.apache.org/jira/browse/DERBY-3892|DERBY-3892]].
  
- For another thing, the statement cache may cause us to need to recompile the statement at
an awkward time, leading to deadlocks -- DERBY-4279
+ For another thing, the statement cache may cause us to need to recompile the statement at
an awkward time, leading to deadlocks -- [[https://issues.apache.org/jira/browse/DERBY-4279|DERBY-4279]]
  

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