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set default_storage_engine='tokudb';
drop table if exists tt;
create table tt (a int, b int, c int, primary key(a));
insert into tt values (1,0,0),(2,0,0),(3,0,1),(4,0,1);
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
analyze table tt;
Table Op Msg_type Msg_text
test.tt analyze status Engine-independent statistics collected
test.tt analyze status OK
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
alter table tt add key (b);
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
tt 1 b 1 b A 4 NULL NULL YES BTREE
analyze table tt;
Table Op Msg_type Msg_text
test.tt analyze status Engine-independent statistics collected
test.tt analyze status OK
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
tt 1 b 1 b A 2 NULL NULL YES BTREE
alter table tt add key (c);
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
tt 1 b 1 b A 2 NULL NULL YES BTREE
tt 1 c 1 c A 4 NULL NULL YES BTREE
analyze table tt;
Table Op Msg_type Msg_text
test.tt analyze status Engine-independent statistics collected
test.tt analyze status OK
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
tt 1 b 1 b A 2 NULL NULL YES BTREE
tt 1 c 1 c A 4 NULL NULL YES BTREE
flush tables;
show indexes from tt;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
tt 0 PRIMARY 1 a A 4 NULL NULL BTREE
tt 1 b 1 b A 2 NULL NULL YES BTREE
tt 1 c 1 c A 4 NULL NULL YES BTREE
drop table tt;
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