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