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<document>
	<properties>
		<title>JDBC Disk Cache</title>
		<author email="asmuts@apache.org">Aaron Smuts</author>
	</properties>

	<body>
		<section name="JDBC Disk Auxiliary Cache">
			<p>
				The JDBC disk cache uses a relational database such as
				MySQL as a persistent store. It works with Oracle, MySQL
				and HSQL. The cache elements are serialized and written
				into a BLOB. Multiple regions can share a single table.
				You can define multiple, differently configured JDBC
				disk caches in one JCS instance. This allows you to use
				different tables for different cache regions.
			</p>

			<subsection name="Example cache.ccf (MySQL)">
				<source>
					<![CDATA[
##############################################################
################## DEFAULT CACHE REGION  #####################
# sets the default aux value for any non configured caches
jcs.default=MYSQL,RCluster
jcs.default.cacheattributes=org.apache.jcs.engine.CompositeCacheAttributes
jcs.default.cacheattributes.MaxObjects=5000
jcs.default.cacheattributes.MemoryCacheName=org.apache.jcs.engine.memory.lru.LRUMemoryCache
jcs.default.cacheattributes.UseMemoryShrinker=true
jcs.default.cacheattributes.MaxMemoryIdleTimeSeconds=7200
jcs.default.cacheattributes.ShrinkerIntervalSeconds=60
jcs.default.elementattributes=org.apache.jcs.engine.ElementAttributes
jcs.default.elementattributes.IsEternal=false
jcs.default.elementattributes.MaxLifeSeconds=14400
jcs.default.elementattributes.IdleTime=14400
jcs.default.elementattributes.IsSpool=true
jcs.default.elementattributes.IsRemote=true
jcs.default.elementattributes.IsLateral=true

##############################################################
################## CACHE REGIONS AVAILABLE ###################

##############################################################
################## AUXILIARY CACHES AVAILABLE ################
# MYSQL disk cache used for flight options
jcs.auxiliary.MYSQL=org.apache.jcs.auxiliary.disk.jdbc.JDBCDiskCacheFactory
jcs.auxiliary.MYSQL.attributes=org.apache.jcs.auxiliary.disk.jdbc.JDBCDiskCacheAttributes
jcs.auxiliary.MYSQL.attributes.userName=myUsername
jcs.auxiliary.MYSQL.attributes.password=myPassword
jcs.auxiliary.MYSQL.attributes.url=${MYSQL}
jcs.auxiliary.MYSQL.attributes.driverClassName=org.gjt.mm.mysql.Driver
jcs.auxiliary.MYSQL.attributes.tableName=JCS_STORE
jcs.auxiliary.MYSQL.attributes.testBeforeInsert=false
jcs.auxiliary.MYSQL.attributes.maxActive=100
jcs.auxiliary.MYSQL.attributes.MaxPurgatorySize=10000000
jcs.auxiliary.MYSQL.attributes.UseDiskShrinker=true
jcs.auxiliary.MYSQL.attributes.ShrinkerIntervalSeconds=1800
jcs.auxiliary.MYSQL.attributes.allowRemoveAll=false
jcs.auxiliary.MYSQL.attributes.EventQueueType=POOLED
jcs.auxiliary.MYSQL.attributes.EventQueuePoolName=disk_cache_event_queue

##############################################################
################## OPTIONAL THREAD POOL CONFIGURATION #########
# Disk Cache pool
thread_pool.disk_cache_event_queue.useBoundary=true
thread_pool.disk_cache_event_queue.boundarySize=1000
thread_pool.disk_cache_event_queue.maximumPoolSize=50
thread_pool.disk_cache_event_queue.minimumPoolSize=10
thread_pool.disk_cache_event_queue.keepAliveTime=3500
thread_pool.disk_cache_event_queue.whenBlockedPolicy=RUN
thread_pool.disk_cache_event_queue.startUpSize=10
        ]]>
				</source>
			</subsection>


			<subsection name="Table Creation Script (MySQL)">
				<source>
					<![CDATA[
drop TABLE JCS_STORE;

CREATE TABLE JCS_STORE
(
  CACHE_KEY                   VARCHAR(250)          NOT NULL,
  REGION                      VARCHAR(250)          NOT NULL,
  ELEMENT                     BLOB,
  CREATE_TIME                 DATETIME,
  CREATE_TIME_SECONDS         BIGINT,
  MAX_LIFE_SECONDS            BIGINT,
  SYSTEM_EXPIRE_TIME_SECONDS  BIGINT,
  IS_ETERNAL                  CHAR(1),
  PRIMARY KEY (CACHE_KEY, REGION)
);

alter table JCS_STORE MAX_ROWS = 10000000;

alter table JCS_STORE AVG_ROW_LENGTH = 2100;

create index JCS_STORE_DELETE_IDX on JCS_STORE (SYSTEM_EXPIRE_TIME_SECONDS,IS_ETERNAL,REGION);
        ]]>
				</source>
			</subsection>
		</section>
	</body>
</document>