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CREATE TABLE t1 (f1 VARCHAR(767) PRIMARY KEY) ENGINE=InnoDB;
CREATE UNIQUE INDEX i63 ON t1(f1);
CREATE UNIQUE INDEX i62 ON t1(f1);
CREATE UNIQUE INDEX i61 ON t1(f1);
CREATE UNIQUE INDEX i60 ON t1(f1);
CREATE UNIQUE INDEX i59 ON t1(f1);
CREATE UNIQUE INDEX i58 ON t1(f1);
CREATE UNIQUE INDEX i57 ON t1(f1);
CREATE UNIQUE INDEX i56 ON t1(f1);
CREATE UNIQUE INDEX i55 ON t1(f1);
CREATE UNIQUE INDEX i54 ON t1(f1);
CREATE UNIQUE INDEX i53 ON t1(f1);
CREATE UNIQUE INDEX i52 ON t1(f1);
CREATE UNIQUE INDEX i51 ON t1(f1);
CREATE UNIQUE INDEX i50 ON t1(f1);
CREATE UNIQUE INDEX i49 ON t1(f1);
CREATE UNIQUE INDEX i48 ON t1(f1);
CREATE UNIQUE INDEX i47 ON t1(f1);
CREATE UNIQUE INDEX i46 ON t1(f1);
CREATE UNIQUE INDEX i45 ON t1(f1);
CREATE UNIQUE INDEX i44 ON t1(f1);
CREATE UNIQUE INDEX i43 ON t1(f1);
CREATE UNIQUE INDEX i42 ON t1(f1);
CREATE UNIQUE INDEX i41 ON t1(f1);
CREATE UNIQUE INDEX i40 ON t1(f1);
CREATE UNIQUE INDEX i39 ON t1(f1);
CREATE UNIQUE INDEX i38 ON t1(f1);
CREATE UNIQUE INDEX i37 ON t1(f1);
CREATE UNIQUE INDEX i36 ON t1(f1);
CREATE UNIQUE INDEX i35 ON t1(f1);
CREATE UNIQUE INDEX i34 ON t1(f1);
CREATE UNIQUE INDEX i33 ON t1(f1);
CREATE UNIQUE INDEX i32 ON t1(f1);
CREATE UNIQUE INDEX i31 ON t1(f1);
CREATE UNIQUE INDEX i30 ON t1(f1);
CREATE UNIQUE INDEX i29 ON t1(f1);
CREATE UNIQUE INDEX i28 ON t1(f1);
CREATE UNIQUE INDEX i27 ON t1(f1);
CREATE UNIQUE INDEX i26 ON t1(f1);
CREATE UNIQUE INDEX i25 ON t1(f1);
CREATE UNIQUE INDEX i24 ON t1(f1);
CREATE UNIQUE INDEX i23 ON t1(f1);
CREATE UNIQUE INDEX i22 ON t1(f1);
CREATE UNIQUE INDEX i21 ON t1(f1);
CREATE UNIQUE INDEX i20 ON t1(f1);
CREATE UNIQUE INDEX i19 ON t1(f1);
CREATE UNIQUE INDEX i18 ON t1(f1);
CREATE UNIQUE INDEX i17 ON t1(f1);
CREATE UNIQUE INDEX i16 ON t1(f1);
CREATE UNIQUE INDEX i15 ON t1(f1);
CREATE UNIQUE INDEX i14 ON t1(f1);
CREATE UNIQUE INDEX i13 ON t1(f1);
CREATE UNIQUE INDEX i12 ON t1(f1);
CREATE UNIQUE INDEX i11 ON t1(f1);
CREATE UNIQUE INDEX i10 ON t1(f1);
CREATE UNIQUE INDEX i9 ON t1(f1);
CREATE UNIQUE INDEX i8 ON t1(f1);
CREATE UNIQUE INDEX i7 ON t1(f1);
CREATE UNIQUE INDEX i6 ON t1(f1);
CREATE UNIQUE INDEX i5 ON t1(f1);
CREATE UNIQUE INDEX i4 ON t1(f1);
CREATE UNIQUE INDEX i3 ON t1(f1);
CREATE UNIQUE INDEX i2 ON t1(f1);
CREATE UNIQUE INDEX i1 ON t1(f1);
INSERT INTO t1 VALUES (REPEAT('a', 767));
SELECT COUNT(*) = 1 FROM t1;
COUNT(*) = 1
1
SELECT LENGTH(f1) = 767 FROM t1;
LENGTH(f1) = 767
1
EXPLAIN SELECT COUNT(*) = 1 FROM t1 FORCE KEY (PRIMARY) WHERE f1 = REPEAT('a', 767);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const PRIMARY PRIMARY 769 const 1 Using index
SELECT COUNT(*) = 1 FROM t1 FORCE KEY (PRIMARY) WHERE f1 = REPEAT('a', 767);
COUNT(*) = 1
1
EXPLAIN SELECT COUNT(*) = 1 FROM t1 FORCE KEY (i1) WHERE f1 = REPEAT('a', 767);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const i1 i1 769 const 1 Using index
SELECT COUNT(*) = 1 FROM t1 FORCE KEY (i1) WHERE f1 = REPEAT('a', 767);
COUNT(*) = 1
1
EXPLAIN SELECT COUNT(*) = 1 FROM t1 FORCE KEY (i63) WHERE f1 = REPEAT('a', 767);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 const i63 i63 769 const 1 Using index
SELECT COUNT(*) = 1 FROM t1 FORCE KEY (i63) WHERE f1 = REPEAT('a', 767);
COUNT(*) = 1
1
INSERT INTO t1 VALUES (REPEAT('b', 767));
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
SELECT COUNT(*) = 2 FROM t1;
COUNT(*) = 2
1
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
DELETE FROM t1 WHERE f1 = REPEAT('b', 767);
SET AUTOCOMMIT=OFF;
START TRANSACTION;
SELECT COUNT(*) = 1 FROM t1;
COUNT(*) = 1
1
INSERT INTO t1 (f1) VALUES (REPEAT('c', 767));
ROLLBACK;
SELECT COUNT(*) = 1 FROM t1;
COUNT(*) = 1
1
START TRANSACTION;
SET AUTOCOMMIT=OFF;
SELECT COUNT(*) = 1 FROM t1;
COUNT(*) = 1
1
START TRANSACTION;
START TRANSACTION;
UPDATE t1 SET f1 = REPEAT('e', 767);
UPDATE t1 SET f1 = REPEAT('f', 767);
COMMIT;
COMMIT;
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
DROP TABLE t1;
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