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Merge work:/home/bk/mysql into mashka.mysql.fi:/home/my/mysql-3.23
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commit
446f23568a
1 changed files with 18 additions and 0 deletions
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@ -1376,6 +1376,24 @@ mysql_execute_command(void)
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start_slave(thd);
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break;
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case SQLCOM_SLAVE_STOP:
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/*
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if the client thread has locked tables, a deadlock is possible.
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Assume that
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- the client thread does LOCK TABLE t READ.
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- then the master updates t.
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- then the SQL slave thread wants to update t,
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so it waits for the client thread because t is locked by it.
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- then the client thread does SLAVE STOP.
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SLAVE STOP waits for the SQL slave thread to terminate its
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update t, which waits for the client thread because t is locked by it.
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To prevent that, refuse SLAVE STOP if the
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client thread has locked tables
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*/
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if (thd->locked_tables || thd->active_transaction())
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{
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send_error(&thd->net,ER_LOCK_OR_ACTIVE_TRANSACTION);
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break;
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}
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stop_slave(thd);
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break;
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