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create table t1 (a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
create table t2 (a int, key(a));
insert into t2 select 2*(A.a + 10*(B.a + 10*C.a)) from t1 A, t1 B, t1 C;
set in_predicate_conversion_threshold= 2000;
set @a="select * from t2 force index (a) where a NOT IN(0";
select count(*) from (select @a:=concat(@a, ',', a) from t2 ) Z;
count(*)
1000
set @a=concat(@a, ')');
insert into t2 values (11),(13),(15);
set @b= concat("explain ", @a);
prepare stmt1 from @b;
execute stmt1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index a a 5 NULL 1003 Using where; Using index
prepare stmt1 from @a;
execute stmt1;
a
11
13
15
set in_predicate_conversion_threshold= default;
drop table t1, t2;
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