jdbc连接MySQL报错Unknown system variable 'query_cache_size'

今天尝试Spring+Spring MVC+MyBatis时，接连MySQL会报错，报错信息如下：

02-Jun-2018 12:46:56.247 警告 [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2] com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@14dcb832 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (2). Last acquisition attempt exception: 
 java.sql.SQLException: Unknown system variable 'query_cache_size'
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:959)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3870)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3806)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2470)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2617)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2546)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2504)
    at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1370)
    at com.mysql.jdbc.ConnectionImpl.loadServerVariables(ConnectionImpl.java:3861)
    at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3289)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2298)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2084)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:795)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:400)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:327)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)

网上查了原因是mysql-connecter-java的版本过低，我由5.1.37改成5.1.44就可以了。

根据官方的说法是

意思是query cache在MySQL5.7.20就已经过时了，而在MySQL8.0之后就已经被移除了。

贴一个stackoverflow上的解答连接stackoverflow上相关问题

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