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SET @ORIG_PAUSE_BACKGROUND_WORK = @@ROCKSDB_PAUSE_BACKGROUND_WORK;
SET GLOBAL ROCKSDB_PAUSE_BACKGROUND_WORK = 1;
DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (
t TEXT,
tt TINYTEXT,
m MEDIUMTEXT,
l LONGTEXT,
PRIMARY KEY t (t(32))
) ENGINE=rocksdb;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 PRIMARY 1 t A 1000 32 NULL LSMTREE
INSERT INTO t1 (t,tt,m,l) VALUES
('','','',''),
('a','b','c','d'),
('b','d','c','b'),
('test1','test2','test3','test4'),
(REPEAT('a',128),REPEAT('b',128),REPEAT('c',128),REPEAT('d',128)),
('abc','def','ghi','jkl'),
('test2','test3','test4','test5'),
('test3','test4','test5','test6'),
(REPEAT('b',128),REPEAT('f',128),REPEAT('e',128),REPEAT('d',128)),
(REPEAT('c',128),REPEAT('b',128),REPEAT('c',128),REPEAT('e',128));
EXPLAIN SELECT SUBSTRING(t,16) AS f FROM t1 WHERE t IN ('test1','test2') ORDER BY f;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY PRIMARY 34 NULL # Using where; Using filesort
SELECT SUBSTRING(t,16) AS f FROM t1 WHERE t IN ('test1','test2') ORDER BY f;
f
EXPLAIN SELECT SUBSTRING(t,16) AS f FROM t1 IGNORE INDEX (PRIMARY) WHERE t IN ('test1','test2') ORDER BY f;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL # Using where; Using filesort
SELECT SUBSTRING(t,16) AS f FROM t1 IGNORE INDEX (PRIMARY) WHERE t IN ('test1','test2') ORDER BY f;
f
DROP TABLE t1;
CREATE TABLE t1 (
t TEXT,
tt TINYTEXT,
m MEDIUMTEXT,
l LONGTEXT,
pk TINYTEXT PRIMARY KEY,
UNIQUE INDEX l_tt (l(256),tt(64))
) ENGINE=rocksdb;
ERROR 42000: BLOB/TEXT column 'pk' used in key specification without a key length
CREATE TABLE t1 (
t TEXT,
tt TINYTEXT,
m MEDIUMTEXT,
l LONGTEXT,
pk MEDIUMTEXT,
PRIMARY KEY mt (pk(1)),
INDEX (m(128))
) ENGINE=rocksdb;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 PRIMARY 1 pk A 1000 1 NULL LSMTREE
t1 1 m 1 m A 500 128 NULL YES LSMTREE
INSERT INTO t1 (t,tt,m,l,pk) VALUES
('','','','','0'),
('a','b','c','d','1'),
('b','d','c','b','2'),
('test1','test2','test3','test4','3'),
(REPEAT('a',128),REPEAT('b',128),REPEAT('c',128),REPEAT('d',128),'4'),
('abc','def','ghi','jkl','5'),
('test2','test3','test4','test5','6'),
('test3','test4','test5','test6','7'),
(REPEAT('b',128),REPEAT('f',128),REPEAT('e',128),REPEAT('d',128),'8'),
(REPEAT('c',128),REPEAT('b',128),REPEAT('c',128),REPEAT('e',128),'9');
EXPLAIN SELECT SUBSTRING(m,128) AS f FROM t1 WHERE m = 'test1' ORDER BY f DESC;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref m m 131 const # Using where; Using filesort
SELECT SUBSTRING(m,128) AS f FROM t1 WHERE m = 'test1' ORDER BY f DESC;
f
DROP TABLE t1;
CREATE TABLE t1 (
b TEXT,
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES
('00000000000000000000000000000000'),
('00000000000000000000000000000001'),
('00000000000000000000000000000002');
SELECT b FROM t1;
b
00000000000000000000000000000000
00000000000000000000000000000001
00000000000000000000000000000002
DROP TABLE t1;
CREATE TABLE t1 (
b TINYTEXT,
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES
('00000000000000000000000000000000'),
('00000000000000000000000000000001'),
('00000000000000000000000000000002');
SELECT b FROM t1;
b
00000000000000000000000000000000
00000000000000000000000000000001
00000000000000000000000000000002
DROP TABLE t1;
CREATE TABLE t1 (
b MEDIUMTEXT,
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES
('00000000000000000000000000000000'),
('00000000000000000000000000000001'),
('00000000000000000000000000000002');
SELECT b FROM t1;
b
00000000000000000000000000000000
00000000000000000000000000000001
00000000000000000000000000000002
DROP TABLE t1;
CREATE TABLE t1 (
b LONGTEXT,
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES
('00000000000000000000000000000000'),
('00000000000000000000000000000001'),
('00000000000000000000000000000002');
SELECT b FROM t1;
b
00000000000000000000000000000000
00000000000000000000000000000001
00000000000000000000000000000002
DROP TABLE t1;
CREATE TABLE t1 (
b LONGTEXT CHARACTER SET "binary" COLLATE "binary",
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES
('00000000000000000000000000000000'),
('00000000000000000000000000000001'),
('00000000000000000000000000000002');
INSERT INTO t1 (b) VALUES (''), (_binary 0x0), (' ');
SELECT hex(b) FROM t1;
hex(b)
00
20
3030303030303030303030303030303030303030303030303030303030303030
3030303030303030303030303030303030303030303030303030303030303031
3030303030303030303030303030303030303030303030303030303030303032
DROP TABLE t1;
CREATE TABLE t1 (
b LONGTEXT CHARACTER SET "latin1" COLLATE "latin1_bin",
PRIMARY KEY b (b(32))
) ENGINE=rocksdb;
INSERT INTO t1 (b) VALUES (''), (_binary 0x0), (' ');
ERROR 23000: Duplicate entry ' ' for key 'PRIMARY'
INSERT INTO t1 (b) VALUES (''), (_binary 0x0);
SELECT hex(b) FROM t1;
hex(b)
00
DROP TABLE t1;
SET GLOBAL ROCKSDB_PAUSE_BACKGROUND_WORK = @ORIG_PAUSE_BACKGROUND_WORK;
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