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43 lines
1.4 KiB
Plaintext
43 lines
1.4 KiB
Plaintext
truncate table performance_schema.events_statements_history_long;
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truncate table performance_schema.events_stages_history_long;
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drop table if exists t0, t1;
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select * from performance_schema.setup_instruments where name like '%show_explain%';
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NAME ENABLED TIMED
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wait/synch/cond/sql/show_explain YES YES
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stage/sql/show explain YES YES
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statement/sql/show_explain YES YES
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# We've got no instances
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select * from performance_schema.cond_instances where name like '%show_explain%';
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NAME OBJECT_INSTANCE_BEGIN
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# Check out if our cond is hit.
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create table t0 (a int);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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connect con1, localhost, root,,;
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connection con1;
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connection default;
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connection con1;
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set @show_explain_probe_select_id=1;
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SET @saved_dbug = @@SESSION.debug_dbug;
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SET debug_dbug='d,show_explain_probe_join_exec_start';
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select count(*) from t0 where a < 100000;
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connection default;
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show explain for $thr2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t0 ALL NULL NULL NULL NULL 10 Using where
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Warnings:
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Note 1003 select count(*) from t0 where a < 100000
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connection con1;
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count(*)
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10
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SET debug_dbug= @saved_dbug;
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select event_name
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from
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performance_schema.events_stages_history_long join
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performance_schema.threads using (thread_id)
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where
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event_name like '%show explain' and
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processlist_id=$thr1;
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event_name
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stage/sql/show explain
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drop table t0;
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