drop table if exists t1; create table t1 SELECT 1,"table 1"; repair table t1 use_frm; Table Op Msg_type Msg_text test.t1 repair warning Number of rows changed from 0 to 1 test.t1 repair status OK alter table t1 ENGINE=HEAP; repair table t1 use_frm; Table Op Msg_type Msg_text test.t1 repair note The storage engine for the table doesn't support repair drop table t1; create table t1(id int PRIMARY KEY, st varchar(10), KEY st_key(st)); insert into t1 values(1, "One"); alter table t1 disable keys; show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment t1 0 PRIMARY 1 id A 1 NULL NULL BTREE t1 1 st_key 1 st A NULL NULL NULL YES BTREE disabled repair table t1 extended; Table Op Msg_type Msg_text test.t1 repair status OK show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment t1 0 PRIMARY 1 id A 1 NULL NULL BTREE t1 1 st_key 1 st A NULL NULL NULL YES BTREE disabled drop table t1; repair table t1 use_frm; Table Op Msg_type Msg_text test.t1 repair Error Table 'test.t1' doesn't exist test.t1 repair status Operation failed create table t1 engine=myisam SELECT 1,"table 1"; flush tables; repair table t1; Table Op Msg_type Msg_text test.t1 repair Error Incorrect file format 't1' test.t1 repair error Corrupt repair table t1 use_frm; Table Op Msg_type Msg_text test.t1 repair warning Number of rows changed from 0 to 1 test.t1 repair status OK drop table t1; CREATE TABLE t1(a INT, KEY(a)); INSERT INTO t1 VALUES(1),(2),(3),(4),(5); SET myisam_repair_threads=2; REPAIR TABLE t1; Table Op Msg_type Msg_text test.t1 repair status OK SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment t1 1 a 1 a A 5 NULL NULL YES BTREE SET myisam_repair_threads=@@global.myisam_repair_threads; DROP TABLE t1; CREATE TABLE t1(a INT); USE mysql; REPAIR TABLE test.t1 USE_FRM; Table Op Msg_type Msg_text test.t1 repair status OK USE test; DROP TABLE t1; CREATE TABLE t1(a CHAR(255), KEY(a)); SET myisam_sort_buffer_size=4096; INSERT INTO t1 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'); Warnings: Error 1034 myisam_sort_buffer_size is too small Error 1034 Number of rows changed from 0 to 157 SET myisam_repair_threads=2; REPAIR TABLE t1; Table Op Msg_type Msg_text test.t1 repair error myisam_sort_buffer_size is too small test.t1 repair warning Number of rows changed from 0 to 157 test.t1 repair status OK SET myisam_repair_threads=@@global.myisam_repair_threads; SET myisam_sort_buffer_size=@@global.myisam_sort_buffer_size; DROP TABLE t1; CREATE TABLE t1(a CHAR(255), KEY(a)); SET myisam_sort_buffer_size=4496; INSERT INTO t1 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'); SET myisam_repair_threads=2; REPAIR TABLE t1; Table Op Msg_type Msg_text test.t1 repair status OK SET myisam_repair_threads=@@global.myisam_repair_threads; SET myisam_sort_buffer_size=@@global.myisam_sort_buffer_size; DROP TABLE t1; End of 4.1 tests # Test with a saved table from 4.1 SHOW TABLE STATUS LIKE 't1'; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 9 Fixed 2 5 10 21474836479 1024 0 NULL # # NULL latin1_swedish_ci NULL SELECT * FROM t1; id 1 2 # Run CHECK TABLE, it should indicate table need a REPAIR TABLE CHECK TABLE t1 FOR UPGRADE; Table Op Msg_type Msg_text test.t1 check error Table upgrade required. Please do "REPAIR TABLE `t1`" or dump/reload to fix it! # REPAIR old table USE_FRM should fail REPAIR TABLE t1 USE_FRM; Table Op Msg_type Msg_text t1 repair error Failed repairing incompatible .frm file # Run REPAIR TABLE to upgrade .frm file REPAIR TABLE t1; Table Op Msg_type Msg_text test.t1 repair status OK SHOW TABLE STATUS LIKE 't1'; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 10 Fixed 2 7 14 1970324836974591 1024 0 NULL # # NULL latin1_swedish_ci NULL SELECT * FROM t1; id 1 2 REPAIR TABLE t1 USE_FRM; Table Op Msg_type Msg_text test.t1 repair warning Number of rows changed from 0 to 2 test.t1 repair status OK SELECT * FROM t1; id 1 2 DROP TABLE t1; DROP TABLE IF EXISTS tt1; CREATE TEMPORARY TABLE tt1 (c1 INT); REPAIR TABLE tt1 USE_FRM; Table Op Msg_type Msg_text tt1 repair error Cannot repair temporary table from .frm file DROP TABLE tt1;