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drop table if exists t0, t1;
SET @old_debug= @@session.debug;
set debug_sync='RESET';
create table t0 (a int) engine=myisam;
insert into t0 values (1),(2),(3),(4),(5),(6),(7),(8);
create table t1 (a int, b int, filler char(100), key(a), key(b));
insert into t1
select A.a+10*B.a + 10*C.a, A.a+10*B.a + 10*C.a, 'filler'
from t0 A, t0 B, t0 C;
#
# Test SHOW EXPLAIN for single-table DELETE
#
set debug_dbug='+d,show_explain_probe_delete_exec_start';
delete from t1 where a<10 and b+1>1000;
show explain for $thr2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 5 NULL 1 Using where
Warnings:
Note 1003 delete from t1 where a<10 and b+1>1000
#
# Test SHOW EXPLAIN for multi-table DELETE
#
set @show_explain_probe_select_id=1;
set debug_dbug='+d,show_explain_probe_do_select';
delete t1 from t1, t0 where t0.a=t1.a and t1.b +1 > 1000;
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 8 Using where
1 SIMPLE t1 ref a a 5 test.t0.a 4 Using where
Warnings:
Note 1003 delete t1 from t1, t0 where t0.a=t1.a and t1.b +1 > 1000
#
# Test SHOW EXPLAIN for single-table UPDATE
#
set debug_dbug='+d,show_explain_probe_update_exec_start';
update t1 set filler='filler-data-2' where a<10 and b+1>1000;
show explain for $thr2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range a a 5 NULL 1 Using where
Warnings:
Note 1003 update t1 set filler='filler-data-2' where a<10 and b+1>1000
drop table t0,t1;
set debug_dbug=@old_debug;
set debug_sync='RESET';
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