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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 (b BINARY,
b20 BINARY(20) PRIMARY KEY,
v16 VARBINARY(16),
v128 VARBINARY(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 Ignored
t1 0 PRIMARY 1 b20 A 1000 NULL NULL LSMTREE NO
INSERT INTO t1 (b,b20,v16,v128) VALUES ('a','char1','varchar1a','varchar1b'),('a','char2','varchar2a','varchar2b'),('b','char3','varchar1a','varchar1b'),('c','char4','varchar3a','varchar3b');
EXPLAIN SELECT HEX(b20) FROM t1 ORDER BY b20;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL PRIMARY 20 NULL # Using index
SELECT HEX(b20) FROM t1 ORDER BY b20;
HEX(b20)
6368617231000000000000000000000000000000
6368617232000000000000000000000000000000
6368617233000000000000000000000000000000
6368617234000000000000000000000000000000
EXPLAIN SELECT HEX(b20) FROM t1 IGNORE INDEX (PRIMARY) ORDER BY b20 DESC;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL # Using filesort
SELECT HEX(b20) FROM t1 ORDER BY b20 DESC;
HEX(b20)
6368617234000000000000000000000000000000
6368617233000000000000000000000000000000
6368617232000000000000000000000000000000
6368617231000000000000000000000000000000
DROP TABLE t1;
CREATE TABLE t1 (b BINARY,
b20 BINARY(20),
v16 VARBINARY(16),
v128 VARBINARY(128),
pk VARBINARY(10) PRIMARY KEY,
INDEX (v16(10))
) 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 Ignored
t1 0 PRIMARY 1 pk A 1000 NULL NULL LSMTREE NO
t1 1 v16 1 v16 A 500 10 NULL YES LSMTREE NO
INSERT INTO t1 (b,b20,v16,v128,pk) VALUES ('a','char1','varchar1a','varchar1b',1),('a','char2','varchar2a','varchar2b',2),('b','char3','varchar1a','varchar1b',3),('c','char4','varchar3a','varchar3b',4),('d','char5','varchar4a','varchar3b',5),('e','char6','varchar2a','varchar3b',6);
INSERT INTO t1 (b,b20,v16,v128,pk) SELECT b,b20,v16,v128,pk+100 FROM t1;
EXPLAIN SELECT HEX(SUBSTRING(v16,0,3)) FROM t1 WHERE v16 LIKE 'varchar%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v16 v16 13 NULL # Using where
SELECT HEX(SUBSTRING(v16,7,3)) FROM t1 WHERE v16 LIKE 'varchar%';
HEX(SUBSTRING(v16,7,3))
723161
723161
723161
723161
723261
723261
723261
723261
723361
723361
723461
723461
EXPLAIN SELECT HEX(SUBSTRING(v16,0,3)) FROM t1 FORCE INDEX (v16) WHERE v16 LIKE 'varchar%';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range v16 v16 13 NULL # Using where
SELECT HEX(SUBSTRING(v16,7,3)) FROM t1 FORCE INDEX (v16) WHERE v16 LIKE 'varchar%';
HEX(SUBSTRING(v16,7,3))
723161
723161
723161
723161
723261
723261
723261
723261
723361
723361
723461
723461
DROP TABLE t1;
SET GLOBAL ROCKSDB_PAUSE_BACKGROUND_WORK = @ORIG_PAUSE_BACKGROUND_WORK;
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