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	Remove one of the major sources of race condiitons in mariadb-test. Normally, mariadb_close() sends COM_QUIT to the server and immediately disconnects. In mariadb-test it means the test can switch to another connection and sends queries to the server before the server even started parsing the COM_QUIT packet and these queries can see the connection as fully active, as it didn't reach dispatch_command yet. This is a major source of instability in tests and many - but not all, still less than a half - tests employ workarounds. The correct one is a pair count_sessions.inc/wait_until_count_sessions.inc. Also very popular was wait_until_disconnected.inc, which was completely useless, because it verifies that the connection is closed, and after disconnect it always is, it didn't verify whether the server processed COM_QUIT. Sadly the placebo was as widely used as the real thing. Let's fix this by making mariadb-test `disconnect` command _to wait_ for the server to confirm. This makes almost all workarounds redundant. In some cases count_sessions.inc/wait_until_count_sessions.inc is still needed, though, as only `disconnect` command is changed: * after external tools, like `exec $MYSQL` * after failed `connect` command * replication, after `STOP SLAVE` * Federated/CONNECT/SPIDER/etc after `DROP TABLE` and also in some XA tests, because an XA transaction is dissociated from the THD very late, after the server has closed the client connection. Collateral cleanups: fix comments, remove some redundant statements: * DROP IF EXISTS if nothing is known to exist * DROP table/view before DROP DATABASE * REVOKE privileges before DROP USER etc
		
			
				
	
	
		
			44 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			44 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
--source include/have_debug.inc
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--source include/have_debug_sync.inc
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create table t0(a int primary key);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t1(a int primary key);
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insert into t1 select A.a + B.a* 10 + C.a * 100 from t0 A, t0 B, t0 C;
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create table t2 (
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  kp1 int,
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  kp2 int,
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  col char(100),
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  key(kp1, kp2)
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);
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insert into t2 select a, a, a from t1;
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select engine from information_schema.tables
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where table_schema=database() and table_name='t2';
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explain 
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select * from t2 where kp1 between 10 and 20 and kp2 +1 >100;
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let $target_id= `select connection_id()`;
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set debug_sync='handler_index_cond_check SIGNAL at_icp_check WAIT_FOR go';
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send
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select * from t2 where kp1 between 10 and 20 and kp2 +1 >100;
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connect (con1, localhost, root,,);
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connection con1;
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set debug_sync='now WAIT_FOR at_icp_check';
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evalp kill query $target_id;
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set debug_sync='now SIGNAL go';
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connection default;
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--error ER_QUERY_INTERRUPTED
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reap;
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set debug_sync='RESET';
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disconnect con1;
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drop table t0,t1,t2;
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