#---------------- Index merge test 1 ------------------------------------------- SET SESSION STORAGE_ENGINE = MyISAM; drop table if exists t0, t1, t2, t3, t4; create table t0 ( key1 int not null, INDEX i1(key1) ); alter table t0 add key2 int not null, add index i2(key2); alter table t0 add key3 int not null, add index i3(key3); alter table t0 add key4 int not null, add index i4(key4); alter table t0 add key5 int not null, add index i5(key5); alter table t0 add key6 int not null, add index i6(key6); alter table t0 add key7 int not null, add index i7(key7); alter table t0 add key8 int not null, add index i8(key8); update t0 set key2=key1,key3=key1,key4=key1,key5=key1,key6=key1,key7=key1,key8=1024-key1; analyze table t0; Table Op Msg_type Msg_text test.t0 analyze status OK explain select * from t0 where key1 < 3 or key1 > 1020; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 range i1 i1 4 NULL 78 Using where explain select * from t0 where key1 < 3 or key2 > 1020; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 45 Using sort_union(i1,i2); Using where select * from t0 where key1 < 3 or key2 > 1020; key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 1023 2 2 2 2 2 2 2 1022 1021 1021 1021 1021 1021 1021 1021 3 1022 1022 1022 1022 1022 1022 1022 2 1023 1023 1023 1023 1023 1023 1023 1 1024 1024 1024 1024 1024 1024 1024 0 explain select * from t0 where key1 < 3 or key2 <4; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 7 Using sort_union(i1,i2); Using where explain select * from t0 where (key1 > 30 and key1<35) or (key2 >32 and key2 < 40); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 11 Using sort_union(i1,i2); Using where select * from t0 where (key1 > 30 and key1<35) or (key2 >32 and key2 < 40); key1 key2 key3 key4 key5 key6 key7 key8 31 31 31 31 31 31 31 993 32 32 32 32 32 32 32 992 33 33 33 33 33 33 33 991 34 34 34 34 34 34 34 990 35 35 35 35 35 35 35 989 36 36 36 36 36 36 36 988 37 37 37 37 37 37 37 987 38 38 38 38 38 38 38 986 39 39 39 39 39 39 39 985 explain select * from t0 ignore index (i2) where key1 < 3 or key2 <4; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1 NULL NULL NULL 1024 Using where explain select * from t0 where (key1 < 3 or key2 <4) and key3 = 50; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ref i1,i2,i3 i3 4 const 1 Using where explain select * from t0 use index (i1,i2) where (key1 < 3 or key2 <4) and key3 = 50; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 7 Using sort_union(i1,i2); Using where explain select * from t0 where (key1 > 1 or key2 > 2); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2 NULL NULL NULL 1024 Using where explain select * from t0 force index (i1,i2) where (key1 > 1 or key2 > 2); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 1024 Using sort_union(i1,i2); Using where explain select * from t0 where key1<3 or key2<3 or (key1>5 and key1<8) or (key1>10 and key1<12) or (key2>100 and key2<110); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 17 Using sort_union(i1,i2); Using where explain select * from t0 where key2 = 45 or key1 <=> null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 range i1,i2 i2 4 NULL 1 Using where explain select * from t0 where key2 = 45 or key1 is not null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2 NULL NULL NULL 1024 Using where explain select * from t0 where key2 = 45 or key1 is null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ref i2 i2 4 const 1 explain select * from t0 where key2=10 or key3=3 or key4 <=> null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i2,i3,i4 i2,i3 4,4 NULL 2 Using union(i2,i3); Using where explain select * from t0 where key2=10 or key3=3 or key4 is null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i2,i3 i2,i3 4,4 NULL 2 Using union(i2,i3); Using where explain select key1 from t0 where (key1 <=> null) or (key2 < 5) or (key3=10) or (key4 <=> null); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i4 i2,i3 4,4 NULL 6 Using sort_union(i2,i3); Using where explain select key1 from t0 where (key1 <=> null) or (key1 < 5) or (key3=10) or (key4 <=> null); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i3,i4 i1,i3 4,4 NULL 6 Using sort_union(i1,i3); Using where explain select * from t0 where (key1 < 3 or key2 < 3) and (key3 < 4 or key4 < 4) and (key5 < 5 or key6 < 5); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i4,i5,i6 i1,i2 4,4 NULL 6 Using sort_union(i1,i2); Using where explain select * from t0 where (key1 < 3 or key2 < 6) and (key1 < 7 or key3 < 4); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3 i1,i2 4,4 NULL 9 Using sort_union(i1,i2); Using where select * from t0 where (key1 < 3 or key2 < 6) and (key1 < 7 or key3 < 4); key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 1023 2 2 2 2 2 2 2 1022 3 3 3 3 3 3 3 1021 4 4 4 4 4 4 4 1020 5 5 5 5 5 5 5 1019 explain select * from t0 where (key1 < 3 or key2 < 3) and (key3 < 4 or key4 < 4) and (key5 < 2 or key6 < 2); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i4,i5,i6 i1,i2 4,4 NULL 6 Using sort_union(i1,i2); Using where explain select * from t0 where (key1 < 3 or key2 < 3) and (key3 < 100); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 range i1,i2,i3 i3 4 NULL 95 Using where explain select * from t0 where (key1 < 3 or key2 < 3) and (key3 < 1000); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2,i3 NULL NULL NULL 1024 Using where explain select * from t0 where ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4)) or key2 > 5; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2,i3 NULL NULL NULL 1024 Using where explain select * from t0 where ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4)) or key1 < 7; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where select * from t0 where ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4)) or key1 < 7; key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 1023 2 2 2 2 2 2 2 1022 3 3 3 3 3 3 3 1021 4 4 4 4 4 4 4 1020 5 5 5 5 5 5 5 1019 6 6 6 6 6 6 6 1018 explain select * from t0 where ((key1 < 4 or key2 < 4) and (key3 <5 or key5 < 4)) or ((key5 < 5 or key6 < 6) and (key7 <7 or key8 < 4)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i5,i6,i7,i8 i1,i2,i5,i6 4,4,4,4 NULL 19 Using sort_union(i1,i2,i5,i6); Using where explain select * from t0 where ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4)) or ((key7 <7 or key8 < 4) and (key5 < 5 or key6 < 6)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i5,i6,i7,i8 i3,i5,i7,i8 4,4,4,4 NULL 20 Using sort_union(i3,i5,i7,i8); Using where explain select * from t0 where ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4)) or ((key3 <7 or key5 < 2) and (key5 < 5 or key6 < 6)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i5,i6 i3,i5 4,4 NULL 11 Using sort_union(i3,i5); Using where explain select * from t0 where ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4)) or (((key3 <7 and key7 < 6) or key5 < 2) and (key5 < 5 or key6 < 6)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i5,i6,i7 i3,i5 4,4 NULL 11 Using sort_union(i3,i5); Using where explain select * from t0 where ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4)) or ((key3 >=5 or key5 < 2) and (key5 < 5 or key6 < 6)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2,i3,i5,i6 NULL NULL NULL 1024 Using where explain select * from t0 force index(i1, i2, i3, i4, i5, i6 ) where ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4)) or ((key3 >=5 or key5 < 2) and (key5 < 5 or key6 < 6)); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2,i3,i5,i6 i3,i5 0,4 NULL 1024 Using sort_union(i3,i5); Using where select * from t0 where key1 < 5 or key8 < 4 order by key1; key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 1023 2 2 2 2 2 2 2 1022 3 3 3 3 3 3 3 1021 4 4 4 4 4 4 4 1020 1021 1021 1021 1021 1021 1021 1021 3 1022 1022 1022 1022 1022 1022 1022 2 1023 1023 1023 1023 1023 1023 1023 1 1024 1024 1024 1024 1024 1024 1024 0 explain select * from t0 where key1 < 5 or key8 < 4 order by key1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i8 i1,i8 4,4 NULL 9 Using sort_union(i1,i8); Using where; Using filesort create table t2 like t0; insert into t2 select * from t0; alter table t2 add index i1_3(key1, key3); alter table t2 add index i2_3(key2, key3); alter table t2 drop index i1; alter table t2 drop index i2; alter table t2 add index i321(key3, key2, key1); explain select key3 from t2 where key1 = 100 or key2 = 100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 index_merge i1_3,i2_3 i1_3,i2_3 4,4 NULL 2 Using sort_union(i1_3,i2_3); Using where explain select key3 from t2 where key1 <100 or key2 < 100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 index i1_3,i2_3 i321 12 NULL 1024 Using where; Using index explain select key7 from t2 where key1 <100 or key2 < 100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 ALL i1_3,i2_3 NULL NULL NULL 1024 Using where create table t4 ( key1a int not null, key1b int not null, key2 int not null, key2_1 int not null, key2_2 int not null, key3 int not null, index i1a (key1a, key1b), index i1b (key1b, key1a), index i2_1(key2, key2_1), index i2_2(key2, key2_1) ); insert into t4 select key1,key1,key1 div 10, key1 % 10, key1 % 10, key1 from t0; select * from t4 where key1a = 3 or key1b = 4; key1a key1b key2 key2_1 key2_2 key3 3 3 0 3 3 3 4 4 0 4 4 4 explain select * from t4 where key1a = 3 or key1b = 4; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t4 index_merge i1a,i1b i1a,i1b 4,4 NULL 2 Using sort_union(i1a,i1b); Using where explain select * from t4 where key2 = 1 and (key2_1 = 1 or key3 = 5); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t4 ref i2_1,i2_2 i2_1 4 const 10 Using where explain select * from t4 where key2 = 1 and (key2_1 = 1 or key2_2 = 5); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t4 ref i2_1,i2_2 i2_1 4 const 10 Using where explain select * from t4 where key2_1 = 1 or key2_2 = 5; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t4 ALL NULL NULL NULL NULL 1024 Using where create table t1 like t0; insert into t1 select * from t0; explain select * from t0 left join t1 on (t0.key1=t1.key1) where t0.key1=3 or t0.key2=4; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 2 Using union(i1,i2); Using where 1 SIMPLE t1 ref i1 i1 4 test.t0.key1 1 select * from t0 left join t1 on (t0.key1=t1.key1) where t0.key1=3 or t0.key2=4; key1 key2 key3 key4 key5 key6 key7 key8 key1 key2 key3 key4 key5 key6 key7 key8 3 3 3 3 3 3 3 1021 3 3 3 3 3 3 3 1021 4 4 4 4 4 4 4 1020 4 4 4 4 4 4 4 1020 explain select * from t0,t1 where (t0.key1=t1.key1) and ( t0.key1=3 or t0.key2=4); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 2 Using union(i1,i2); Using where 1 SIMPLE t1 ref i1 i1 4 test.t0.key1 1 explain select * from t0,t1 where (t0.key1=t1.key1) and (t0.key1=3 or t0.key2=4) and t1.key1<200; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ALL i1,i2 NULL NULL NULL 1024 Using where 1 SIMPLE t1 ref i1 i1 4 test.t0.key1 1 explain select * from t0,t1 where (t0.key1=t1.key1) and (t0.key1=3 or t0.key2<4) and t1.key1=2; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ref i1,i2 i1 4 const 1 Using where 1 SIMPLE t1 ref i1 i1 4 const 1 explain select * from t0,t1 where t0.key1 = 5 and (t1.key1 = t0.key1 or t1.key8 = t0.key1); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 ref i1 i1 4 const 1 1 SIMPLE t1 index_merge i1,i8 i1,i8 4,4 NULL 2 Using union(i1,i8); Using where explain select * from t0,t1 where t0.key1 < 3 and (t1.key1 = t0.key1 or t1.key8 = t0.key1); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 range i1 i1 4 NULL 3 Using where 1 SIMPLE t1 ALL i1,i8 NULL NULL NULL 1024 Range checked for each record (index map: 0x81) explain select * from t1 where key1=3 or key2=4 union select * from t1 where key1<4 or key3=5; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY t1 index_merge i1,i2 i1,i2 4,4 NULL 2 Using union(i1,i2); Using where 2 UNION t1 index_merge i1,i3 i1,i3 4,4 NULL 5 Using sort_union(i1,i3); Using where NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL explain select * from (select * from t1 where key1 = 3 or key2 =3) as Z where key8 >5; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY <derived2> system NULL NULL NULL NULL 1 2 DERIVED t1 index_merge i1,i2 i1,i2 4,4 NULL 2 Using union(i1,i2); Using where create table t3 like t0; insert into t3 select * from t0; alter table t3 add key9 int not null, add index i9(key9); alter table t3 add keyA int not null, add index iA(keyA); alter table t3 add keyB int not null, add index iB(keyB); alter table t3 add keyC int not null, add index iC(keyC); update t3 set key9=key1,keyA=key1,keyB=key1,keyC=key1; explain select * from t3 where key1=1 or key2=2 or key3=3 or key4=4 or key5=5 or key6=6 or key7=7 or key8=8 or key9=9 or keyA=10 or keyB=11 or keyC=12; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t3 index_merge i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC 4,4,4,4,4,4,4,4,4,4,4,4 NULL 12 Using union(i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC); Using where select * from t3 where key1=1 or key2=2 or key3=3 or key4=4 or key5=5 or key6=6 or key7=7 or key8=8 or key9=9 or keyA=10 or keyB=11 or keyC=12; key1 key2 key3 key4 key5 key6 key7 key8 key9 keyA keyB keyC 1 1 1 1 1 1 1 1023 1 1 1 1 2 2 2 2 2 2 2 1022 2 2 2 2 3 3 3 3 3 3 3 1021 3 3 3 3 4 4 4 4 4 4 4 1020 4 4 4 4 5 5 5 5 5 5 5 1019 5 5 5 5 6 6 6 6 6 6 6 1018 6 6 6 6 7 7 7 7 7 7 7 1017 7 7 7 7 9 9 9 9 9 9 9 1015 9 9 9 9 10 10 10 10 10 10 10 1014 10 10 10 10 11 11 11 11 11 11 11 1013 11 11 11 11 12 12 12 12 12 12 12 1012 12 12 12 12 1016 1016 1016 1016 1016 1016 1016 8 1016 1016 1016 1016 explain select * from t0 where key1 < 3 or key2 < 4; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t0 index_merge i1,i2 i1,i2 4,4 NULL 7 Using sort_union(i1,i2); Using where select * from t0 where key1 < 3 or key2 < 4; key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 1023 2 2 2 2 2 2 2 1022 3 3 3 3 3 3 3 1021 update t0 set key8=123 where key1 < 3 or key2 < 4; select * from t0 where key1 < 3 or key2 < 4; key1 key2 key3 key4 key5 key6 key7 key8 1 1 1 1 1 1 1 123 2 2 2 2 2 2 2 123 3 3 3 3 3 3 3 123 delete from t0 where key1 < 3 or key2 < 4; select * from t0 where key1 < 3 or key2 < 4; key1 key2 key3 key4 key5 key6 key7 key8 select count(*) from t0; count(*) 1021 drop table t4; create table t4 (a int); insert into t4 values (1),(4),(3); set @save_join_buffer_size=@@join_buffer_size; set join_buffer_size= 4000; explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A force index(i1,i2), t0 as B force index (i1,i2) where (A.key1 < 500000 or A.key2 < 3) and (B.key1 < 500000 or B.key2 < 3); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE A index_merge i1,i2 i1,i2 4,4 NULL 1013 Using sort_union(i1,i2); Using where 1 SIMPLE B index_merge i1,i2 i1,i2 4,4 NULL 1013 Using sort_union(i1,i2); Using where select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A force index(i1,i2), t0 as B force index (i1,i2) where (A.key1 < 500000 or A.key2 < 3) and (B.key1 < 500000 or B.key2 < 3); max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 10240 update t0 set key1=1; explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A force index(i1,i2), t0 as B force index (i1,i2) where (A.key1 = 1 or A.key2 = 1) and (B.key1 = 1 or B.key2 = 1); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE A index_merge i1,i2 i1,i2 4,4 NULL 1020 Using union(i1,i2); Using where 1 SIMPLE B index_merge i1,i2 i1,i2 4,4 NULL 1020 Using union(i1,i2); Using where select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A force index(i1,i2), t0 as B force index (i1,i2) where (A.key1 = 1 or A.key2 = 1) and (B.key1 = 1 or B.key2 = 1); max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 8194 alter table t0 add filler1 char(200), add filler2 char(200), add filler3 char(200); update t0 set key2=1, key3=1, key4=1, key5=1,key6=1,key7=1 where key7 < 500; explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A, t0 as B where (A.key1 = 1 and A.key2 = 1 and A.key3 = 1 and A.key4=1 and A.key5=1 and A.key6=1 and A.key7 = 1 or A.key8=1) and (B.key1 = 1 and B.key2 = 1 and B.key3 = 1 and B.key4=1 and B.key5=1 and B.key6=1 and B.key7 = 1 or B.key8=1); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE A index_merge i1,i2,i3,i4,i5,i6,i7?,i8 i2,i3,i4,i5,i6,i7?,i8 X NULL # Using union(intersect(i2,i3,i4,i5,i6,i7?),i8); Using where 1 SIMPLE B index_merge i1,i2,i3,i4,i5,i6,i7?,i8 i2,i3,i4,i5,i6,i7?,i8 X NULL # Using union(intersect(i2,i3,i4,i5,i6,i7?),i8); Using where select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) from t0 as A, t0 as B where (A.key1 = 1 and A.key2 = 1 and A.key3 = 1 and A.key4=1 and A.key5=1 and A.key6=1 and A.key7 = 1 or A.key8=1) and (B.key1 = 1 and B.key2 = 1 and B.key3 = 1 and B.key4=1 and B.key5=1 and B.key6=1 and B.key7 = 1 or B.key8=1); max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 8186 set join_buffer_size= @save_join_buffer_size; drop table t0, t1, t2, t3, t4; CREATE TABLE t1 ( cola char(3) not null, colb char(3) not null, filler char(200), key(cola), key(colb) ); INSERT INTO t1 VALUES ('foo','bar', 'ZZ'),('fuz','baz', 'ZZ'); OPTIMIZE TABLE t1; Table Op Msg_type Msg_text test.t1 optimize status OK select count(*) from t1; count(*) 8704 explain select * from t1 WHERE cola = 'foo' AND colb = 'bar'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge cola,colb cola,colb 3,3 NULL 32 Using intersect(cola,colb); Using where explain select * from t1 force index(cola,colb) WHERE cola = 'foo' AND colb = 'bar'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge cola,colb cola,colb 3,3 NULL 32 Using intersect(cola,colb); Using where drop table t1; create table t0 (a int); insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); create table t1 ( a int, b int, filler1 char(200), filler2 char(200), key(a),key(b) ); insert into t1 select @v:= A.a, @v, 't1', 'filler2' from t0 A, t0 B, t0 C; create table t2 like t1; create table t3 ( a int, b int, filler1 char(200), filler2 char(200), key(a),key(b) ) engine=merge union=(t1,t2); explain select * from t1 where a=1 and b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge a,b a,b 5,5 NULL # Using intersect(a,b); Using where explain select * from t3 where a=1 and b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t3 index_merge a,b a,b 5,5 NULL # Using intersect(a,b); Using where drop table t3; drop table t0, t1, t2; CREATE TABLE t1(a INT); INSERT INTO t1 VALUES(1); CREATE TABLE t2(a INT, b INT, dummy CHAR(16) DEFAULT '', KEY(a), KEY(b)); INSERT INTO t2(a,b) VALUES (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0),(0,0), (1,2); LOCK TABLES t1 WRITE, t2 WRITE; INSERT INTO t2(a,b) VALUES(1,2); SELECT t2.a FROM t1,t2 WHERE t2.b=2 AND t2.a=1; a 1 1 UNLOCK TABLES; DROP TABLE t1, t2; #---------------- ROR-index_merge tests ----------------------- SET SESSION STORAGE_ENGINE = MyISAM; drop table if exists t0,t1,t2; create table t1 ( /* Field names reflect value(rowid) distribution, st=STairs, swt= SaWTooth */ st_a int not null default 0, swt1a int not null default 0, swt2a int not null default 0, st_b int not null default 0, swt1b int not null default 0, swt2b int not null default 0, /* fields/keys for row retrieval tests */ key1 int, key2 int, key3 int, key4 int, /* make rows much bigger then keys */ filler1 char (200), filler2 char (200), filler3 char (200), filler4 char (200), filler5 char (200), filler6 char (200), /* order of keys is important */ key sta_swt12a(st_a,swt1a,swt2a), key sta_swt1a(st_a,swt1a), key sta_swt2a(st_a,swt2a), key sta_swt21a(st_a,swt2a,swt1a), key st_a(st_a), key stb_swt1a_2b(st_b,swt1b,swt2a), key stb_swt1b(st_b,swt1b), key st_b(st_b), key(key1), key(key2), key(key3), key(key4) ) ; create table t0 as select * from t1; # Printing of many insert into t0 values (....) disabled. alter table t1 disable keys; # Printing of many insert into t1 select .... from t0 disabled. # Printing of many insert into t1 (...) values (....) disabled. alter table t1 enable keys; select count(*) from t1; count(*) 64801 explain select key1,key2 from t1 where key1=100 and key2=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL 77 Using intersect(key1,key2); Using where; Using index select key1,key2 from t1 where key1=100 and key2=100; key1 key2 100 100 explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 154 Using union(intersect(key1,key2),intersect(key3,key4)); Using where select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; key1 key2 key3 key4 filler1 100 100 100 100 key1-key2-key3-key4 insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, -1, -1, 'key1-key2'); insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, 100, 100, 'key4-key3'); explain select key1,key2,filler1 from t1 where key1=100 and key2=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL 77 Using intersect(key1,key2); Using where select key1,key2,filler1 from t1 where key1=100 and key2=100; key1 key2 filler1 100 100 key1-key2-key3-key4 100 100 key1-key2 explain select key1,key2 from t1 where key1=100 and key2=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL 77 Using intersect(key1,key2); Using where; Using index select key1,key2 from t1 where key1=100 and key2=100; key1 key2 100 100 100 100 explain select key1,key2,key3,key4 from t1 where key1=100 and key2=100 or key3=100 and key4=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 154 Using union(intersect(key1,key2),intersect(key3,key4)); Using where select key1,key2,key3,key4 from t1 where key1=100 and key2=100 or key3=100 and key4=100; key1 key2 key3 key4 100 100 100 100 100 100 -1 -1 -1 -1 100 100 explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 154 Using union(intersect(key1,key2),intersect(key3,key4)); Using where select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; key1 key2 key3 key4 filler1 100 100 100 100 key1-key2-key3-key4 100 100 -1 -1 key1-key2 -1 -1 100 100 key4-key3 explain select key1,key2,key3 from t1 where key1=100 and key2=100 and key3=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3 key1,key2,key3 5,5,5 NULL 2 Using intersect(key1,key2,key3); Using where; Using index select key1,key2,key3 from t1 where key1=100 and key2=100 and key3=100; key1 key2 key3 100 100 100 insert into t1 (key1,key2,key3,key4,filler1) values (101,101,101,101, 'key1234-101'); explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=101; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3 key1,key2,key3 5,5,5 NULL 83 Using union(intersect(key1,key2),key3); Using where select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=101; key1 key2 key3 key4 filler1 100 100 100 100 key1-key2-key3-key4 100 100 -1 -1 key1-key2 101 101 101 101 key1234-101 select key1,key2, filler1 from t1 where key1=100 and key2=100; key1 key2 filler1 100 100 key1-key2-key3-key4 100 100 key1-key2 update t1 set filler1='to be deleted' where key1=100 and key2=100; update t1 set key1=200,key2=200 where key1=100 and key2=100; delete from t1 where key1=200 and key2=200; select key1,key2,filler1 from t1 where key2=100 and key2=200; key1 key2 filler1 explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 152 Using union(intersect(key1,key2),intersect(key3,key4)); Using where select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; key1 key2 key3 key4 filler1 -1 -1 100 100 key4-key3 delete from t1 where key3=100 and key4=100; explain select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key1,key2,key3,key4 5,5,5,5 NULL 152 Using union(intersect(key1,key2),intersect(key3,key4)); Using where select key1,key2,key3,key4,filler1 from t1 where key1=100 and key2=100 or key3=100 and key4=100; key1 key2 key3 key4 filler1 explain select key1,key2 from t1 where key1=100 and key2=100; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 5,5 NULL 76 Using intersect(key1,key2); Using where; Using index select key1,key2 from t1 where key1=100 and key2=100; key1 key2 insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-1'); insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-2'); insert into t1 (key1, key2, key3, key4, filler1) values (100, 100, 200, 200,'key1-key2-key3-key4-3'); explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 136 Using union(key3,intersect(key1,key2),key4); Using where select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; key1 key2 key3 key4 filler1 100 100 200 200 key1-key2-key3-key4-3 100 100 200 200 key1-key2-key3-key4-2 100 100 200 200 key1-key2-key3-key4-1 insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, -1, 200,'key4'); explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 146 Using union(key3,intersect(key1,key2),key4); Using where select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; key1 key2 key3 key4 filler1 100 100 200 200 key1-key2-key3-key4-3 100 100 200 200 key1-key2-key3-key4-2 100 100 200 200 key1-key2-key3-key4-1 -1 -1 -1 200 key4 insert into t1 (key1, key2, key3, key4, filler1) values (-1, -1, 200, -1,'key3'); explain select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2,key3,key4 key3,key1,key2,key4 5,5,5,5 NULL 156 Using union(key3,intersect(key1,key2),key4); Using where select key1,key2,key3,key4,filler1 from t1 where key3=200 or (key1=100 and key2=100) or key4=200; key1 key2 key3 key4 filler1 100 100 200 200 key1-key2-key3-key4-3 100 100 200 200 key1-key2-key3-key4-2 100 100 200 200 key1-key2-key3-key4-1 -1 -1 -1 200 key4 -1 -1 200 -1 key3 explain select * from t1 where st_a=1 and st_b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b st_a,st_b 4,4 NULL 3515 Using intersect(st_a,st_b); Using where explain select st_a,st_b from t1 where st_a=1 and st_b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b st_a,st_b 4,4 NULL 3515 Using intersect(st_a,st_b); Using where; Using index explain select st_a from t1 ignore index (st_a) where st_a=1 and st_b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,stb_swt1a_2b,stb_swt1b,st_b st_b 4 const 15093 Using where explain select * from t1 where st_a=1 and swt1a=1 and swt2a=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a sta_swt21a 12 const,const,const 971 explain select * from t1 where st_b=1 and swt1b=1 and swt2b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref stb_swt1a_2b,stb_swt1b,st_b stb_swt1a_2b 8 const,const 3879 Using where explain select * from t1 where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt12a,stb_swt1a_2b 12,12 NULL 58 Using intersect(sta_swt12a,stb_swt1a_2b); Using where explain select * from t1 ignore index (sta_swt21a, stb_swt1a_2b) where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,st_a,stb_swt1b,st_b sta_swt12a,stb_swt1b 12,8 NULL 58 Using intersect(sta_swt12a,stb_swt1b); Using where explain select * from t1 ignore index (sta_swt21a, sta_swt12a, stb_swt1a_2b) where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt1a,sta_swt2a,st_a,stb_swt1b,st_b sta_swt1a,sta_swt2a,stb_swt1b 8,8,8 NULL 57 Using intersect(sta_swt1a,sta_swt2a,stb_swt1b); Using where explain select * from t1 ignore index (sta_swt21a, sta_swt12a, stb_swt1a_2b, stb_swt1b) where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1 and swt2b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt1a,sta_swt2a,st_a,st_b sta_swt1a,sta_swt2a,st_b 8,8,4 NULL 223 Using intersect(sta_swt1a,sta_swt2a,st_b); Using where explain select * from t1 where st_a=1 and swt1a=1 and swt2a=1 and st_b=1 and swt1b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt12a,stb_swt1a_2b 12,12 NULL 58 Using intersect(sta_swt12a,stb_swt1a_2b); Using where explain select * from t1 where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 232 Using intersect(sta_swt1a,stb_swt1b); Using where explain select st_a from t1 where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 232 Using intersect(sta_swt1a,stb_swt1b); Using where; Using index explain select st_a from t1 where st_a=1 and swt1a=1 and st_b=1 and swt1b=1 and swt1b=1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge sta_swt12a,sta_swt1a,sta_swt2a,sta_swt21a,st_a,stb_swt1a_2b,stb_swt1b,st_b sta_swt1a,stb_swt1b 8,8 NULL 232 Using intersect(sta_swt1a,stb_swt1b); Using where; Using index drop table t0,t1; create table t2 ( a char(10), b char(10), filler1 char(255), filler2 char(255), key(a(5)), key(b(5)) ); select count(a) from t2 where a='BBBBBBBB'; count(a) 4 select count(a) from t2 where b='BBBBBBBB'; count(a) 4 expla_or_bin select count(a_or_b) from t2 where a_or_b='AAAAAAAA' a_or_bnd a_or_b='AAAAAAAA'; id select_type ta_or_ba_or_ble type possia_or_ble_keys key key_len ref rows Extra_or_b 1 SIMPLE t2 ref a_or_b,a_or_b a_or_b 6 const 4 Using where select count(a) from t2 where a='AAAAAAAA' and b='AAAAAAAA'; count(a) 4 select count(a) from t2 ignore index(a,b) where a='AAAAAAAA' and b='AAAAAAAA'; count(a) 4 insert into t2 values ('ab', 'ab', 'uh', 'oh'); explain select a from t2 where a='ab'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t2 ref a a 6 const 1 Using where drop table t2; #---------------- Index merge test 2 ------------------------------------------- SET SESSION STORAGE_ENGINE = MyISAM; drop table if exists t1,t2; create table t1 ( key1 int not null, key2 int not null, INDEX i1(key1), INDEX i2(key2) ); explain select * from t1 where key1 < 5 or key2 > 197; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where select * from t1 where key1 < 5 or key2 > 197; key1 key2 0 200 1 199 2 198 3 197 4 196 explain select * from t1 where key1 < 3 or key2 > 195; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where select * from t1 where key1 < 3 or key2 > 195; key1 key2 0 200 1 199 2 198 3 197 4 196 alter table t1 add str1 char (255) not null, add zeroval int not null default 0, add str2 char (255) not null, add str3 char (255) not null; update t1 set str1='aaa', str2='bbb', str3=concat(key2, '-', key1 div 2, '_' ,if(key1 mod 2 = 0, 'a', 'A')); alter table t1 add primary key (str1, zeroval, str2, str3); explain select * from t1 where key1 < 5 or key2 > 197; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where select * from t1 where key1 < 5 or key2 > 197; key1 key2 str1 zeroval str2 str3 0 200 aaa 0 bbb 200-0_a 1 199 aaa 0 bbb 199-0_A 2 198 aaa 0 bbb 198-1_a 3 197 aaa 0 bbb 197-1_A 4 196 aaa 0 bbb 196-2_a explain select * from t1 where key1 < 3 or key2 > 195; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i2 i1,i2 4,4 NULL 10 Using sort_union(i1,i2); Using where select * from t1 where key1 < 3 or key2 > 195; key1 key2 str1 zeroval str2 str3 0 200 aaa 0 bbb 200-0_a 1 199 aaa 0 bbb 199-0_A 2 198 aaa 0 bbb 198-1_a 3 197 aaa 0 bbb 197-1_A 4 196 aaa 0 bbb 196-2_a drop table t1; create table t1 ( pk integer not null auto_increment primary key, key1 integer, key2 integer not null, filler char (200), index (key1), index (key2) ); show warnings; Level Code Message explain select pk from t1 where key1 = 1 and key2 = 1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,key2 key1 5 const 4 Using where select pk from t1 where key2 = 1 and key1 = 1; pk 26 27 select pk from t1 ignore index(key1,key2) where key2 = 1 and key1 = 1; pk 26 27 drop table t1; create table t1 ( pk int primary key auto_increment, key1a int, key2a int, key1b int, key2b int, dummy1 int, dummy2 int, dummy3 int, dummy4 int, key3a int, key3b int, filler1 char (200), index i1(key1a, key1b), index i2(key2a, key2b), index i3(key3a, key3b) ); create table t2 (a int); insert into t2 values (0),(1),(2),(3),(4),(NULL); insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b) select A.a, B.a, C.a, D.a, C.a, D.a from t2 A,t2 B,t2 C, t2 D; insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b) select key1a, key1b, key2a, key2b, key3a, key3b from t1; insert into t1 (key1a, key1b, key2a, key2b, key3a, key3b) select key1a, key1b, key2a, key2b, key3a, key3b from t1; analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status OK select count(*) from t1; count(*) 5184 explain select count(*) from t1 where key1a = 2 and key1b is null and key2a = 2 and key2b is null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i2 i1,i2 10,10 NULL 2 Using intersect(i1,i2); Using where; Using index select count(*) from t1 where key1a = 2 and key1b is null and key2a = 2 and key2b is null; count(*) 4 explain select count(*) from t1 where key1a = 2 and key1b is null and key3a = 2 and key3b is null; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i1,i3 i1,i3 10,10 NULL 2 Using intersect(i1,i3); Using where; Using index select count(*) from t1 where key1a = 2 and key1b is null and key3a = 2 and key3b is null; count(*) 4 drop table t1,t2; create table t1 ( id1 int, id2 date , index idx2 (id1,id2), index idx1 (id2) ); insert into t1 values(1,'20040101'), (2,'20040102'); select * from t1 where id1 = 1 and id2= '20040101'; id1 id2 1 2004-01-01 drop table t1; drop view if exists v1; CREATE TABLE t1 ( `oid` int(11) unsigned NOT NULL auto_increment, `fk_bbk_niederlassung` int(11) unsigned NOT NULL, `fk_wochentag` int(11) unsigned NOT NULL, `uhrzeit_von` time NOT NULL COMMENT 'HH:MM', `uhrzeit_bis` time NOT NULL COMMENT 'HH:MM', `geloescht` tinyint(4) NOT NULL, `version` int(5) NOT NULL, PRIMARY KEY (`oid`), KEY `fk_bbk_niederlassung` (`fk_bbk_niederlassung`), KEY `fk_wochentag` (`fk_wochentag`), KEY `ix_version` (`version`) ) DEFAULT CHARSET=latin1; insert into t1 values (1, 38, 1, '08:00:00', '13:00:00', 0, 1), (2, 38, 2, '08:00:00', '13:00:00', 0, 1), (3, 38, 3, '08:00:00', '13:00:00', 0, 1), (4, 38, 4, '08:00:00', '13:00:00', 0, 1), (5, 38, 5, '08:00:00', '13:00:00', 0, 1), (6, 38, 5, '08:00:00', '13:00:00', 1, 2), (7, 38, 3, '08:00:00', '13:00:00', 1, 2), (8, 38, 1, '08:00:00', '13:00:00', 1, 2), (9, 38, 2, '08:00:00', '13:00:00', 1, 2), (10, 38, 4, '08:00:00', '13:00:00', 1, 2), (11, 38, 1, '08:00:00', '13:00:00', 0, 3), (12, 38, 2, '08:00:00', '13:00:00', 0, 3), (13, 38, 3, '08:00:00', '13:00:00', 0, 3), (14, 38, 4, '08:00:00', '13:00:00', 0, 3), (15, 38, 5, '08:00:00', '13:00:00', 0, 3), (16, 38, 4, '08:00:00', '13:00:00', 0, 4), (17, 38, 5, '08:00:00', '13:00:00', 0, 4), (18, 38, 1, '08:00:00', '13:00:00', 0, 4), (19, 38, 2, '08:00:00', '13:00:00', 0, 4), (20, 38, 3, '08:00:00', '13:00:00', 0, 4), (21, 7, 1, '08:00:00', '13:00:00', 0, 1), (22, 7, 2, '08:00:00', '13:00:00', 0, 1), (23, 7, 3, '08:00:00', '13:00:00', 0, 1), (24, 7, 4, '08:00:00', '13:00:00', 0, 1), (25, 7, 5, '08:00:00', '13:00:00', 0, 1); create view v1 as select zeit1.oid AS oid, zeit1.fk_bbk_niederlassung AS fk_bbk_niederlassung, zeit1.fk_wochentag AS fk_wochentag, zeit1.uhrzeit_von AS uhrzeit_von, zeit1.uhrzeit_bis AS uhrzeit_bis, zeit1.geloescht AS geloescht, zeit1.version AS version from t1 zeit1 where (zeit1.version = (select max(zeit2.version) AS `max(version)` from t1 zeit2 where ((zeit1.fk_bbk_niederlassung = zeit2.fk_bbk_niederlassung) and (zeit1.fk_wochentag = zeit2.fk_wochentag) and (zeit1.uhrzeit_von = zeit2.uhrzeit_von) and (zeit1.uhrzeit_bis = zeit2.uhrzeit_bis) ) ) ) and (zeit1.geloescht = 0); select * from v1 where oid = 21; oid fk_bbk_niederlassung fk_wochentag uhrzeit_von uhrzeit_bis geloescht version 21 7 1 08:00:00 13:00:00 0 1 drop view v1; drop table t1; CREATE TABLE t1( t_cpac varchar(2) NOT NULL, t_vers varchar(4) NOT NULL, t_rele varchar(2) NOT NULL, t_cust varchar(4) NOT NULL, filler1 char(250) default NULL, filler2 char(250) default NULL, PRIMARY KEY (t_cpac,t_vers,t_rele,t_cust), UNIQUE KEY IX_4 (t_cust,t_cpac,t_vers,t_rele), KEY IX_5 (t_vers,t_rele,t_cust) ); insert into t1 values ('tm','2.5 ','a ',' ','',''), ('tm','2.5U','a ','stnd','',''), ('da','3.3 ','b ',' ','',''), ('da','3.3U','b ','stnd','',''), ('tl','7.6 ','a ',' ','',''), ('tt','7.6 ','a ',' ','',''), ('bc','B61 ','a ',' ','',''), ('bp','B61 ','a ',' ','',''), ('ca','B61 ','a ',' ','',''), ('ci','B61 ','a ',' ','',''), ('cp','B61 ','a ',' ','',''), ('dm','B61 ','a ',' ','',''), ('ec','B61 ','a ',' ','',''), ('ed','B61 ','a ',' ','',''), ('fm','B61 ','a ',' ','',''), ('nt','B61 ','a ',' ','',''), ('qm','B61 ','a ',' ','',''), ('tc','B61 ','a ',' ','',''), ('td','B61 ','a ',' ','',''), ('tf','B61 ','a ',' ','',''), ('tg','B61 ','a ',' ','',''), ('ti','B61 ','a ',' ','',''), ('tp','B61 ','a ',' ','',''), ('ts','B61 ','a ',' ','',''), ('wh','B61 ','a ',' ','',''), ('bc','B61U','a ','stnd','',''), ('bp','B61U','a ','stnd','',''), ('ca','B61U','a ','stnd','',''), ('ci','B61U','a ','stnd','',''), ('cp','B61U','a ','stnd','',''), ('dm','B61U','a ','stnd','',''), ('ec','B61U','a ','stnd','',''), ('fm','B61U','a ','stnd','',''), ('nt','B61U','a ','stnd','',''), ('qm','B61U','a ','stnd','',''), ('tc','B61U','a ','stnd','',''), ('td','B61U','a ','stnd','',''), ('tf','B61U','a ','stnd','',''), ('tg','B61U','a ','stnd','',''), ('ti','B61U','a ','stnd','',''), ('tp','B61U','a ','stnd','',''), ('ts','B61U','a ','stnd','',''), ('wh','B61U','a ','stnd','',''); show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `t_cpac` varchar(2) NOT NULL, `t_vers` varchar(4) NOT NULL, `t_rele` varchar(2) NOT NULL, `t_cust` varchar(4) NOT NULL, `filler1` char(250) DEFAULT NULL, `filler2` char(250) DEFAULT NULL, PRIMARY KEY (`t_cpac`,`t_vers`,`t_rele`,`t_cust`), UNIQUE KEY `IX_4` (`t_cust`,`t_cpac`,`t_vers`,`t_rele`), KEY `IX_5` (`t_vers`,`t_rele`,`t_cust`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 select t_vers,t_rele,t_cust,filler1 from t1 where t_vers = '7.6'; t_vers t_rele t_cust filler1 7.6 a 7.6 a select t_vers,t_rele,t_cust,filler1 from t1 where t_vers = '7.6' and t_rele='a' and t_cust = ' '; t_vers t_rele t_cust filler1 7.6 a 7.6 a drop table t1; create table t1 ( pk int(11) not null auto_increment, a int(11) not null default '0', b int(11) not null default '0', c int(11) not null default '0', filler1 datetime, filler2 varchar(15), filler3 longtext, kp1 varchar(4), kp2 varchar(7), kp3 varchar(2), kp4 varchar(4), kp5 varchar(7), filler4 char(1), primary key (pk), key idx1(a,b,c), key idx2(c), key idx3(kp1,kp2,kp3,kp4,kp5) ) default charset=latin1; set @fill=NULL; SELECT COUNT(*) FROM t1 WHERE b = 0 AND a = 0 AND c = 13286427 AND kp1='279' AND kp2='ELM0678' AND kp3='6' AND kp4='10' AND kp5 = 'R '; COUNT(*) 1 drop table t1; create table t1 ( key1 int not null, key2 int not null default 0, key3 int not null default 0 ); insert into t1(key1) values (1),(2),(3),(4),(5),(6),(7),(8); set @d=8; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; insert into t1 (key1) select key1+@d from t1; set @d=@d*2; alter table t1 add index i2(key2); alter table t1 add index i3(key3); update t1 set key2=key1,key3=key1; explain select * from t1 where (key3 > 30 and key3<35) or (key2 >32 and key2 < 40); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge i2,i3 i3,i2 4,4 NULL 11 Using sort_union(i3,i2); Using where select * from t1 where (key3 > 30 and key3<35) or (key2 >32 and key2 < 40); key1 key2 key3 31 31 31 32 32 32 33 33 33 34 34 34 35 35 35 36 36 36 37 37 37 38 38 38 39 39 39 drop table t1; #---------------- 2-sweeps read Index merge test 2 ------------------------------- SET SESSION STORAGE_ENGINE = MyISAM; drop table if exists t1; create table t1 ( pk int primary key, key1 int, key2 int, filler char(200), filler2 char(200), index(key1), index(key2) ); select * from t1 where (key1 >= 2 and key1 <= 10) or (pk >= 4 and pk <=8 ); pk key1 key2 filler filler2 10 10 10 filler-data filler-data-2 9 9 9 filler-data filler-data-2 8 8 8 filler-data filler-data-2 7 7 7 filler-data filler-data-2 6 6 6 filler-data filler-data-2 5 5 5 filler-data filler-data-2 4 4 4 filler-data filler-data-2 3 3 3 filler-data filler-data-2 2 2 2 filler-data filler-data-2 set @maxv=1000; select * from t1 where (pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10) or key1=18 or key1=60; pk key1 key2 filler filler2 1000 1000 1000 filler-data filler-data-2 999 999 999 filler-data filler-data-2 998 998 998 filler-data filler-data-2 997 997 997 filler-data filler-data-2 996 996 996 filler-data filler-data-2 995 995 995 filler-data filler-data-2 994 994 994 filler-data filler-data-2 993 993 993 filler-data filler-data-2 992 992 992 filler-data filler-data-2 991 991 991 filler-data filler-data-2 60 60 60 filler-data filler-data-2 54 54 54 filler-data filler-data-2 53 53 53 filler-data filler-data-2 52 52 52 filler-data filler-data-2 51 51 51 filler-data filler-data-2 50 50 50 filler-data filler-data-2 18 18 18 filler-data filler-data-2 14 14 14 filler-data filler-data-2 13 13 13 filler-data filler-data-2 12 12 12 filler-data filler-data-2 11 11 11 filler-data filler-data-2 4 4 4 filler-data filler-data-2 3 3 3 filler-data filler-data-2 2 2 2 filler-data filler-data-2 1 1 1 filler-data filler-data-2 select * from t1 where (pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10) or key1 < 3 or key1 > @maxv-11; pk key1 key2 filler filler2 1000 1000 1000 filler-data filler-data-2 999 999 999 filler-data filler-data-2 998 998 998 filler-data filler-data-2 997 997 997 filler-data filler-data-2 996 996 996 filler-data filler-data-2 995 995 995 filler-data filler-data-2 994 994 994 filler-data filler-data-2 993 993 993 filler-data filler-data-2 992 992 992 filler-data filler-data-2 991 991 991 filler-data filler-data-2 990 990 990 filler-data filler-data-2 54 54 54 filler-data filler-data-2 53 53 53 filler-data filler-data-2 52 52 52 filler-data filler-data-2 51 51 51 filler-data filler-data-2 50 50 50 filler-data filler-data-2 14 14 14 filler-data filler-data-2 13 13 13 filler-data filler-data-2 12 12 12 filler-data filler-data-2 11 11 11 filler-data filler-data-2 4 4 4 filler-data filler-data-2 3 3 3 filler-data filler-data-2 2 2 2 filler-data filler-data-2 1 1 1 filler-data filler-data-2 select * from t1 where (pk < 5) or (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (pk > @maxv-10) or (key1 < 5) or (key1 > 10 and key1 < 15) or (key1 >= 50 and key1 < 55 ) or (key1 > @maxv-10); pk key1 key2 filler filler2 1000 1000 1000 filler-data filler-data-2 999 999 999 filler-data filler-data-2 998 998 998 filler-data filler-data-2 997 997 997 filler-data filler-data-2 996 996 996 filler-data filler-data-2 995 995 995 filler-data filler-data-2 994 994 994 filler-data filler-data-2 993 993 993 filler-data filler-data-2 992 992 992 filler-data filler-data-2 991 991 991 filler-data filler-data-2 54 54 54 filler-data filler-data-2 53 53 53 filler-data filler-data-2 52 52 52 filler-data filler-data-2 51 51 51 filler-data filler-data-2 50 50 50 filler-data filler-data-2 14 14 14 filler-data filler-data-2 13 13 13 filler-data filler-data-2 12 12 12 filler-data filler-data-2 11 11 11 filler-data filler-data-2 4 4 4 filler-data filler-data-2 3 3 3 filler-data filler-data-2 2 2 2 filler-data filler-data-2 1 1 1 filler-data filler-data-2 select * from t1 where (pk > 10 and pk < 15) or (pk >= 50 and pk < 55 ) or (key1 < 5) or (key1 > @maxv-10); pk key1 key2 filler filler2 1000 1000 1000 filler-data filler-data-2 999 999 999 filler-data filler-data-2 998 998 998 filler-data filler-data-2 997 997 997 filler-data filler-data-2 996 996 996 filler-data filler-data-2 995 995 995 filler-data filler-data-2 994 994 994 filler-data filler-data-2 993 993 993 filler-data filler-data-2 992 992 992 filler-data filler-data-2 991 991 991 filler-data filler-data-2 54 54 54 filler-data filler-data-2 53 53 53 filler-data filler-data-2 52 52 52 filler-data filler-data-2 51 51 51 filler-data filler-data-2 50 50 50 filler-data filler-data-2 14 14 14 filler-data filler-data-2 13 13 13 filler-data filler-data-2 12 12 12 filler-data filler-data-2 11 11 11 filler-data filler-data-2 4 4 4 filler-data filler-data-2 3 3 3 filler-data filler-data-2 2 2 2 filler-data filler-data-2 1 1 1 filler-data filler-data-2 drop table t1; #---------------- Clustered PK ROR-index_merge tests ----------------------------- SET SESSION STORAGE_ENGINE = MyISAM; drop table if exists t1; create table t1 ( pk1 int not null, pk2 int not null, key1 int not null, key2 int not null, pktail1ok int not null, pktail2ok int not null, pktail3bad int not null, pktail4bad int not null, pktail5bad int not null, pk2copy int not null, badkey int not null, filler1 char (200), filler2 char (200), key (key1), key (key2), /* keys with tails from CPK members */ key (pktail1ok, pk1), key (pktail2ok, pk1, pk2), key (pktail3bad, pk2, pk1), key (pktail4bad, pk1, pk2copy), key (pktail5bad, pk1, pk2, pk2copy), primary key (pk1, pk2) ); explain select * from t1 where pk1 = 1 and pk2 < 80 and key1=0; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 range PRIMARY,key1 PRIMARY 8 NULL 7 Using where select * from t1 where pk1 = 1 and pk2 < 80 and key1=0; pk1 pk2 key1 key2 pktail1ok pktail2ok pktail3bad pktail4bad pktail5bad pk2copy badkey filler1 filler2 1 10 0 0 0 0 0 0 0 10 0 filler-data-10 filler2 1 11 0 0 0 0 0 0 0 11 0 filler-data-11 filler2 1 12 0 0 0 0 0 0 0 12 0 filler-data-12 filler2 1 13 0 0 0 0 0 0 0 13 0 filler-data-13 filler2 1 14 0 0 0 0 0 0 0 14 0 filler-data-14 filler2 1 15 0 0 0 0 0 0 0 15 0 filler-data-15 filler2 1 16 0 0 0 0 0 0 0 16 0 filler-data-16 filler2 1 17 0 0 0 0 0 0 0 17 0 filler-data-17 filler2 1 18 0 0 0 0 0 0 0 18 0 filler-data-18 filler2 1 19 0 0 0 0 0 0 0 19 0 filler-data-19 filler2 explain select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where select pk1,pk2 from t1 where key1 = 10 and key2=10 and 2*pk1+1 < 2*96+1; pk1 pk2 95 59 95 58 95 57 95 56 95 55 95 54 95 53 95 52 95 51 95 50 explain select * from t1 where badkey=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1 key1 4 const 91 Using where explain select * from t1 where pk1 < 7500 and key1 = 10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref PRIMARY,key1 key1 4 const ROWS Using where explain select * from t1 where pktail1ok=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,pktail1ok pktail1ok 4 const 76 Using where explain select * from t1 where pktail2ok=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,pktail2ok pktail2ok 4 const 82 Using where explain select * from t1 where (pktail2ok=1 and pk1< 50000) or key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge PRIMARY,key1,pktail2ok pktail2ok,key1 8,4 NULL 173 Using sort_union(pktail2ok,key1); Using where explain select * from t1 where pktail3bad=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,pktail3bad pktail3bad 4 const 73 Using where explain select * from t1 where pktail4bad=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,pktail4bad pktail4bad 4 const 82 Using where explain select * from t1 where pktail5bad=1 and key1=10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 ref key1,pktail5bad pktail5bad 4 const 70 Using where explain select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 index_merge key1,key2 key1,key2 4,4 NULL 1 Using intersect(key1,key2); Using where select pk1,pk2,key1,key2 from t1 where key1 = 10 and key2=10 limit 10; pk1 pk2 key1 key2 104 49 10 10 104 48 10 10 104 47 10 10 104 46 10 10 104 45 10 10 104 44 10 10 104 43 10 10 104 42 10 10 104 41 10 10 104 40 10 10 drop table t1; create table t1 ( RUNID varchar(22), SUBMITNR varchar(5), ORDERNR char(1), PROGRAMM varchar(8), TESTID varchar(4), UCCHECK char(1), ETEXT varchar(80), ETEXT_TYPE char(1), INFO char(1), SEVERITY tinyint(3), TADIRFLAG char(1), PRIMARY KEY (RUNID,SUBMITNR,ORDERNR,PROGRAMM,TESTID,UCCHECK), KEY `TVERM~KEY` (PROGRAMM,TESTID,UCCHECK) ) DEFAULT CHARSET=latin1; update t1 set `ETEXT` = '', `ETEXT_TYPE`='', `INFO`='', `SEVERITY`='', `TADIRFLAG`='' WHERE `RUNID`= '' AND `SUBMITNR`= '' AND `ORDERNR`='' AND `PROGRAMM`='' AND `TESTID`='' AND `UCCHECK`=''; drop table t1;