drop table if exists t1; set names latin1; select 'hello',"'hello'",'""hello""','''h''e''l''l''o''',"hel""lo",'hel\'lo'; hello 'hello' ""hello"" 'h'e'l'l'o' hel"lo hel'lo hello 'hello' ""hello"" 'h'e'l'l'o' hel"lo hel'lo select 'hello' 'monty'; hello hellomonty select length('\n\t\r\b\0\_\%\\'); length('\n\t\r\b\0\_\%\\') 10 select bit_length('\n\t\r\b\0\_\%\\'); bit_length('\n\t\r\b\0\_\%\\') 80 select char_length('\n\t\r\b\0\_\%\\'); char_length('\n\t\r\b\0\_\%\\') 10 select length(_latin1'\n\t\n\b\0\\_\\%\\'); length(_latin1'\n\t\n\b\0\\_\\%\\') 10 select concat('monty',' was here ','again'),length('hello'),char(ascii('h')),ord('h'); concat('monty',' was here ','again') length('hello') char(ascii('h')) ord('h') monty was here again 5 h 104 select locate('he','hello'),locate('he','hello',2),locate('lo','hello',2) ; locate('he','hello') locate('he','hello',2) locate('lo','hello',2) 1 0 4 select instr('hello','HE'), instr('hello',binary 'HE'), instr(binary 'hello','HE'); instr('hello','HE') instr('hello',binary 'HE') instr(binary 'hello','HE') 1 0 0 select position(binary 'll' in 'hello'),position('a' in binary 'hello'); position(binary 'll' in 'hello') position('a' in binary 'hello') 3 0 select left('hello',2),right('hello',2),substring('hello',2,2),mid('hello',1,5) ; left('hello',2) right('hello',2) substring('hello',2,2) mid('hello',1,5) he lo el hello select concat('',left(right(concat('what ',concat('is ','happening')),9),4),'',substring('monty',5,1)) ; concat('',left(right(concat('what ',concat('is ','happening')),9),4),'',substring('monty',5,1)) happy select substring_index('www.tcx.se','.',-2),substring_index('www.tcx.se','.',1); substring_index('www.tcx.se','.',-2) substring_index('www.tcx.se','.',1) tcx.se www select substring_index('www.tcx.se','tcx',1),substring_index('www.tcx.se','tcx',-1); substring_index('www.tcx.se','tcx',1) substring_index('www.tcx.se','tcx',-1) www. .se select substring_index('.tcx.se','.',-2),substring_index('.tcx.se','.tcx',-1); substring_index('.tcx.se','.',-2) substring_index('.tcx.se','.tcx',-1) tcx.se .se select concat(':',ltrim(' left '),':',rtrim(' right '),':'); concat(':',ltrim(' left '),':',rtrim(' right '),':') :left : right: select concat(':',trim(LEADING FROM ' left'),':',trim(TRAILING FROM ' right '),':'); concat(':',trim(LEADING FROM ' left'),':',trim(TRAILING FROM ' right '),':') :left: right: select concat(':',trim(' m '),':',trim(BOTH FROM ' y '),':',trim('*' FROM '*s*'),':'); concat(':',trim(' m '),':',trim(BOTH FROM ' y '),':',trim('*' FROM '*s*'),':') :m:y:s: select concat(':',trim(BOTH 'ab' FROM 'ababmyabab'),':',trim(BOTH '*' FROM '***sql'),':'); concat(':',trim(BOTH 'ab' FROM 'ababmyabab'),':',trim(BOTH '*' FROM '***sql'),':') :my:sql: select concat(':',trim(LEADING '.*' FROM '.*my'),':',trim(TRAILING '.*' FROM 'sql.*.*'),':'); concat(':',trim(LEADING '.*' FROM '.*my'),':',trim(TRAILING '.*' FROM 'sql.*.*'),':') :my:sql: select TRIM("foo" FROM "foo"), TRIM("foo" FROM "foook"), TRIM("foo" FROM "okfoo"); TRIM("foo" FROM "foo") TRIM("foo" FROM "foook") TRIM("foo" FROM "okfoo") ok ok select concat_ws(', ','monty','was here','again'); concat_ws(', ','monty','was here','again') monty, was here, again select concat_ws(NULL,'a'),concat_ws(',',NULL,''); concat_ws(NULL,'a') concat_ws(',',NULL,'') NULL select concat_ws(',','',NULL,'a'); concat_ws(',','',NULL,'a') ,a SELECT CONCAT('"',CONCAT_WS('";"',repeat('a',60),repeat('b',60),repeat('c',60),repeat('d',100)), '"'); CONCAT('"',CONCAT_WS('";"',repeat('a',60),repeat('b',60),repeat('c',60),repeat('d',100)), '"') "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb";"cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc";"dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd" select insert('txs',2,1,'hi'),insert('is ',4,0,'a'),insert('txxxxt',2,4,'es'); insert('txs',2,1,'hi') insert('is ',4,0,'a') insert('txxxxt',2,4,'es') this is a test select replace('aaaa','a','b'),replace('aaaa','aa','b'),replace('aaaa','a','bb'),replace('aaaa','','b'),replace('bbbb','a','c'); replace('aaaa','a','b') replace('aaaa','aa','b') replace('aaaa','a','bb') replace('aaaa','','b') replace('bbbb','a','c') bbbb bb bbbbbbbb aaaa bbbb select replace(concat(lcase(concat('THIS',' ','IS',' ','A',' ')),ucase('false'),' ','test'),'FALSE','REAL') ; replace(concat(lcase(concat('THIS',' ','IS',' ','A',' ')),ucase('false'),' ','test'),'FALSE','REAL') this is a REAL test select soundex(''),soundex('he'),soundex('hello all folks'),soundex('#3556 in bugdb'); soundex('') soundex('he') soundex('hello all folks') soundex('#3556 in bugdb') H000 H4142 I51231 select 'mood' sounds like 'mud'; 'mood' sounds like 'mud' 1 select 'Glazgo' sounds like 'Liverpool'; 'Glazgo' sounds like 'Liverpool' 0 select null sounds like 'null'; null sounds like 'null' NULL select 'null' sounds like null; 'null' sounds like null NULL select null sounds like null; null sounds like null NULL select md5('hello'); md5('hello') 5d41402abc4b2a76b9719d911017c592 select crc32("123"); crc32("123") 2286445522 select sha('abc'); sha('abc') a9993e364706816aba3e25717850c26c9cd0d89d select sha1('abc'); sha1('abc') a9993e364706816aba3e25717850c26c9cd0d89d select aes_decrypt(aes_encrypt('abc','1'),'1'); aes_decrypt(aes_encrypt('abc','1'),'1') abc select aes_decrypt(aes_encrypt('abc','1'),1); aes_decrypt(aes_encrypt('abc','1'),1) abc select aes_encrypt(NULL,"a"); aes_encrypt(NULL,"a") NULL select aes_encrypt("a",NULL); aes_encrypt("a",NULL) NULL select aes_decrypt(NULL,"a"); aes_decrypt(NULL,"a") NULL select aes_decrypt("a",NULL); aes_decrypt("a",NULL) NULL select aes_decrypt("a","a"); aes_decrypt("a","a") NULL select aes_decrypt(aes_encrypt("","a"),"a"); aes_decrypt(aes_encrypt("","a"),"a") select repeat('monty',5),concat('*',space(5),'*'); repeat('monty',5) concat('*',space(5),'*') montymontymontymontymonty * * select reverse('abc'),reverse('abcd'); reverse('abc') reverse('abcd') cba dcba select rpad('a',4,'1'),rpad('a',4,'12'),rpad('abcd',3,'12'), rpad(11, 10 , 22), rpad("ab", 10, 22); rpad('a',4,'1') rpad('a',4,'12') rpad('abcd',3,'12') rpad(11, 10 , 22) rpad("ab", 10, 22) a111 a121 abc 1122222222 ab22222222 select lpad('a',4,'1'),lpad('a',4,'12'),lpad('abcd',3,'12'), lpad(11, 10 , 22); lpad('a',4,'1') lpad('a',4,'12') lpad('abcd',3,'12') lpad(11, 10 , 22) 111a 121a abc 2222222211 select rpad(741653838,17,'0'),lpad(741653838,17,'0'); rpad(741653838,17,'0') lpad(741653838,17,'0') 74165383800000000 00000000741653838 select rpad('abcd',7,'ab'),lpad('abcd',7,'ab'); rpad('abcd',7,'ab') lpad('abcd',7,'ab') abcdaba abaabcd select rpad('abcd',1,'ab'),lpad('abcd',1,'ab'); rpad('abcd',1,'ab') lpad('abcd',1,'ab') a a select rpad('STRING', 20, CONCAT('p','a','d') ); rpad('STRING', 20, CONCAT('p','a','d') ) STRINGpadpadpadpadpa select lpad('STRING', 20, CONCAT('p','a','d') ); lpad('STRING', 20, CONCAT('p','a','d') ) padpadpadpadpaSTRING select LEAST(NULL,'HARRY','HARRIOT',NULL,'HAROLD'),GREATEST(NULL,'HARRY','HARRIOT',NULL,'HAROLD'); LEAST(NULL,'HARRY','HARRIOT',NULL,'HAROLD') GREATEST(NULL,'HARRY','HARRIOT',NULL,'HAROLD') HAROLD HARRY select least(1,2,3) | greatest(16,32,8), least(5,4)*1,greatest(-1.0,1.0)*1,least(3,2,1)*1.0,greatest(1,1.1,1.0),least("10",9),greatest("A","B","0"); least(1,2,3) | greatest(16,32,8) least(5,4)*1 greatest(-1.0,1.0)*1 least(3,2,1)*1.0 greatest(1,1.1,1.0) least("10",9) greatest("A","B","0") 33 4 1.0 1.0 1.1 9 B select decode(encode(repeat("a",100000),"monty"),"monty")=repeat("a",100000); decode(encode(repeat("a",100000),"monty"),"monty")=repeat("a",100000) 1 select decode(encode("abcdef","monty"),"monty")="abcdef"; decode(encode("abcdef","monty"),"monty")="abcdef" 1 select quote('\'\"\\test'); quote('\'\"\\test') '\'"\\test' select quote(concat('abc\'', '\\cba')); quote(concat('abc\'', '\\cba')) 'abc\'\\cba' select quote(1/0), quote('\0\Z'); quote(1/0) quote('\0\Z') NULL '\0\Z' select length(quote(concat(char(0),"test"))); length(quote(concat(char(0),"test"))) 8 select hex(quote(concat(char(224),char(227),char(230),char(231),char(232),char(234),char(235)))); hex(quote(concat(char(224),char(227),char(230),char(231),char(232),char(234),char(235)))) 27E0E3E6E7E8EAEB27 select unhex(hex("foobar")), hex(unhex("1234567890ABCDEF")), unhex("345678"), unhex(NULL); unhex(hex("foobar")) hex(unhex("1234567890ABCDEF")) unhex("345678") unhex(NULL) foobar 1234567890ABCDEF 4Vx NULL select hex(unhex("1")), hex(unhex("12")), hex(unhex("123")), hex(unhex("1234")), hex(unhex("12345")), hex(unhex("123456")); hex(unhex("1")) hex(unhex("12")) hex(unhex("123")) hex(unhex("1234")) hex(unhex("12345")) hex(unhex("123456")) 01 12 0123 1234 012345 123456 select length(unhex(md5("abrakadabra"))); length(unhex(md5("abrakadabra"))) 16 select concat('a', quote(NULL)); concat('a', quote(NULL)) aNULL select reverse(""); reverse("") select insert("aa",100,1,"b"),insert("aa",1,3,"b"),left("aa",-1),substring("a",1,2); insert("aa",100,1,"b") insert("aa",1,3,"b") left("aa",-1) substring("a",1,2) aa b a select elt(2,1),field(NULL,"a","b","c"),reverse(""); elt(2,1) field(NULL,"a","b","c") reverse("") NULL 0 select locate("a","b",2),locate("","a",1); locate("a","b",2) locate("","a",1) 0 1 select ltrim("a"),rtrim("a"),trim(BOTH "" from "a"),trim(BOTH " " from "a"); ltrim("a") rtrim("a") trim(BOTH "" from "a") trim(BOTH " " from "a") a a a a select concat("1","2")|0,concat("1",".5")+0.0; concat("1","2")|0 concat("1",".5")+0.0 12 1.5 select substring_index("www.tcx.se","",3); substring_index("www.tcx.se","",3) select length(repeat("a",100000000)),length(repeat("a",1000*64)); length(repeat("a",100000000)) length(repeat("a",1000*64)) NULL 64000 Warnings: Warning 1301 Result of repeat() was larger than max_allowed_packet (1048576) - truncated select position("0" in "baaa" in (1)),position("0" in "1" in (1,2,3)),position("sql" in ("mysql")); position("0" in "baaa" in (1)) position("0" in "1" in (1,2,3)) position("sql" in ("mysql")) 1 0 3 select position(("1" in (1,2,3)) in "01"); position(("1" in (1,2,3)) in "01") 2 select length(repeat("a",65500)),length(concat(repeat("a",32000),repeat("a",32000))),length(replace("aaaaa","a",concat(repeat("a",10000)))),length(insert(repeat("a",40000),1,30000,repeat("b",50000))); length(repeat("a",65500)) length(concat(repeat("a",32000),repeat("a",32000))) length(replace("aaaaa","a",concat(repeat("a",10000)))) length(insert(repeat("a",40000),1,30000,repeat("b",50000))) 65500 64000 50000 60000 select length(repeat("a",1000000)),length(concat(repeat("a",32000),repeat("a",32000),repeat("a",32000))),length(replace("aaaaa","a",concat(repeat("a",32000)))),length(insert(repeat("a",48000),1,1000,repeat("a",48000))); length(repeat("a",1000000)) length(concat(repeat("a",32000),repeat("a",32000),repeat("a",32000))) length(replace("aaaaa","a",concat(repeat("a",32000)))) length(insert(repeat("a",48000),1,1000,repeat("a",48000))) 1000000 96000 160000 95000 create table t1 ( domain char(50) ); insert into t1 VALUES ("hello.de" ), ("test.de" ); select domain from t1 where concat('@', trim(leading '.' from concat('.', domain))) = '@hello.de'; domain hello.de select domain from t1 where concat('@', trim(leading '.' from concat('.', domain))) = '@test.de'; domain test.de drop table t1; CREATE TABLE t1 ( id int(10) unsigned NOT NULL, title varchar(255) default NULL, prio int(10) unsigned default NULL, category int(10) unsigned default NULL, program int(10) unsigned default NULL, bugdesc text, created datetime default NULL, modified timestamp(14) NOT NULL, bugstatus int(10) unsigned default NULL, submitter int(10) unsigned default NULL ) ENGINE=MyISAM; INSERT INTO t1 VALUES (1,'Link',1,1,1,'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa','2001-02-28 08:40:16',20010228084016,0,4); SELECT CONCAT('"',CONCAT_WS('";"',title,prio,category,program,bugdesc,created,modified+0,bugstatus,submitter), '"') FROM t1; CONCAT('"',CONCAT_WS('";"',title,prio,category,program,bugdesc,created,modified+0,bugstatus,submitter), '"') "Link";"1";"1";"1";"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";"2001-02-28 08:40:16";"20010228084016";"0";"4" SELECT CONCAT('"',CONCAT_WS('";"',title,prio,category,program,bugstatus,submitter), '"') FROM t1; CONCAT('"',CONCAT_WS('";"',title,prio,category,program,bugstatus,submitter), '"') "Link";"1";"1";"1";"0";"4" SELECT CONCAT_WS('";"',title,prio,category,program,bugdesc,created,modified+0,bugstatus,submitter) FROM t1; CONCAT_WS('";"',title,prio,category,program,bugdesc,created,modified+0,bugstatus,submitter) Link";"1";"1";"1";"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";"2001-02-28 08:40:16";"20010228084016";"0";"4 SELECT bugdesc, REPLACE(bugdesc, 'xxxxxxxxxxxxxxxxxxxx', 'bbbbbbbbbbbbbbbbbbbb') from t1 group by bugdesc; bugdesc REPLACE(bugdesc, 'xxxxxxxxxxxxxxxxxxxx', 'bbbbbbbbbbbbbbbbbbbb') aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa drop table t1; CREATE TABLE t1 (id int(11) NOT NULL auto_increment, tmp text NOT NULL, KEY id (id)) ENGINE=MyISAM; INSERT INTO t1 VALUES (1, 'a545f661efdd1fb66fdee3aab79945bf'); SELECT 1 FROM t1 WHERE tmp=AES_DECRYPT(tmp,"password"); 1 DROP TABLE t1; CREATE TABLE t1 ( wid int(10) unsigned NOT NULL auto_increment, data_podp date default NULL, status_wnio enum('nowy','podp','real','arch') NOT NULL default 'nowy', PRIMARY KEY(wid) ); INSERT INTO t1 VALUES (8,NULL,'real'); INSERT INTO t1 VALUES (9,NULL,'nowy'); SELECT elt(status_wnio,data_podp) FROM t1 GROUP BY wid; elt(status_wnio,data_podp) NULL NULL DROP TABLE t1; CREATE TABLE t1 (title text) ENGINE=MyISAM; INSERT INTO t1 VALUES ('Congress reconvenes in September to debate welfare and adult education'); INSERT INTO t1 VALUES ('House passes the CAREERS bill'); SELECT CONCAT("</a>",RPAD("",(55 - LENGTH(title)),".")) from t1; CONCAT("</a>",RPAD("",(55 - LENGTH(title)),".")) NULL </a>.......................... DROP TABLE t1; CREATE TABLE t1 (i int, j int); INSERT INTO t1 VALUES (1,1),(2,2); SELECT DISTINCT i, ELT(j, '345', '34') FROM t1; i ELT(j, '345', '34') 1 345 2 34 DROP TABLE t1; create table t1(a char(4)); insert into t1 values ('one'),(NULL),('two'),('four'); select a, quote(a), isnull(quote(a)), quote(a) is null, ifnull(quote(a), 'n') from t1; a quote(a) isnull(quote(a)) quote(a) is null ifnull(quote(a), 'n') one 'one' 0 0 'one' NULL NULL 0 0 NULL two 'two' 0 0 'two' four 'four' 0 0 'four' drop table t1; select trim(trailing 'foo' from 'foo'); trim(trailing 'foo' from 'foo') select trim(leading 'foo' from 'foo'); trim(leading 'foo' from 'foo') select quote(ltrim(concat(' ', 'a'))); quote(ltrim(concat(' ', 'a'))) 'a' select quote(trim(concat(' ', 'a'))); quote(trim(concat(' ', 'a'))) 'a' CREATE TABLE t1 SELECT 1 UNION SELECT 2 UNION SELECT 3; SELECT QUOTE('A') FROM t1; QUOTE('A') 'A' 'A' 'A' DROP TABLE t1; select 1=_latin1'1'; 1=_latin1'1' 1 select _latin1'1'=1; _latin1'1'=1 1 select _latin2'1'=1; _latin2'1'=1 1 select 1=_latin2'1'; 1=_latin2'1' 1 select _latin1'1'=_latin2'1'; ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation '=' select row('a','b','c') = row('a','b','c'); row('a','b','c') = row('a','b','c') 1 select row('A','b','c') = row('a','b','c'); row('A','b','c') = row('a','b','c') 1 select row('A' COLLATE latin1_bin,'b','c') = row('a','b','c'); row('A' COLLATE latin1_bin,'b','c') = row('a','b','c') 0 select row('A','b','c') = row('a' COLLATE latin1_bin,'b','c'); row('A','b','c') = row('a' COLLATE latin1_bin,'b','c') 0 select row('A' COLLATE latin1_general_ci,'b','c') = row('a' COLLATE latin1_bin,'b','c'); ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT) and (latin1_bin,EXPLICIT) for operation '=' select concat(_latin1'a',_latin2'a'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation 'concat' select concat(_latin1'a',_latin2'a',_latin5'a'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE), (latin5_turkish_ci,COERCIBLE) for operation 'concat' select concat(_latin1'a',_latin2'a',_latin5'a',_latin7'a'); ERROR HY000: Illegal mix of collations for operation 'concat' select concat_ws(_latin1'a',_latin2'a'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation 'concat_ws' select FIELD('b','A','B'); FIELD('b','A','B') 2 select FIELD('B','A','B'); FIELD('B','A','B') 2 select FIELD('b' COLLATE latin1_bin,'A','B'); FIELD('b' COLLATE latin1_bin,'A','B') 0 select FIELD('b','A' COLLATE latin1_bin,'B'); FIELD('b','A' COLLATE latin1_bin,'B') 0 select FIELD(_latin2'b','A','B'); ERROR HY000: Illegal mix of collations (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'field' select FIELD('b',_latin2'A','B'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'field' select FIELD('b',_latin2'A','B',1); FIELD('b',_latin2'A','B',1) 1 select POSITION(_latin1'B' IN _latin1'abcd'); POSITION(_latin1'B' IN _latin1'abcd') 2 select POSITION(_latin1'B' IN _latin1'abcd' COLLATE latin1_bin); POSITION(_latin1'B' IN _latin1'abcd' COLLATE latin1_bin) 0 select POSITION(_latin1'B' COLLATE latin1_bin IN _latin1'abcd'); POSITION(_latin1'B' COLLATE latin1_bin IN _latin1'abcd') 0 select POSITION(_latin1'B' COLLATE latin1_general_ci IN _latin1'abcd' COLLATE latin1_bin); ERROR HY000: Illegal mix of collations (latin1_bin,EXPLICIT) and (latin1_general_ci,EXPLICIT) for operation 'locate' select POSITION(_latin1'B' IN _latin2'abcd'); ERROR HY000: Illegal mix of collations (latin2_general_ci,COERCIBLE) and (latin1_swedish_ci,COERCIBLE) for operation 'locate' select FIND_IN_SET(_latin1'B',_latin1'a,b,c,d'); FIND_IN_SET(_latin1'B',_latin1'a,b,c,d') 2 select FIND_IN_SET(_latin1'B' COLLATE latin1_general_ci,_latin1'a,b,c,d' COLLATE latin1_bin); ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT) and (latin1_bin,EXPLICIT) for operation 'find_in_set' select FIND_IN_SET(_latin1'B',_latin2'a,b,c,d'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation 'find_in_set' select SUBSTRING_INDEX(_latin1'abcdabcdabcd',_latin1'd',2); SUBSTRING_INDEX(_latin1'abcdabcdabcd',_latin1'd',2) abcdabc select SUBSTRING_INDEX(_latin1'abcdabcdabcd',_latin2'd',2); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation 'substr_index' select SUBSTRING_INDEX(_latin1'abcdabcdabcd' COLLATE latin1_general_ci,_latin1'd' COLLATE latin1_bin,2); ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT) and (latin1_bin,EXPLICIT) for operation 'substr_index' select _latin1'B' between _latin1'a' and _latin1'c'; _latin1'B' between _latin1'a' and _latin1'c' 1 select _latin1'B' collate latin1_bin between _latin1'a' and _latin1'c'; _latin1'B' collate latin1_bin between _latin1'a' and _latin1'c' 0 select _latin1'B' between _latin1'a' collate latin1_bin and _latin1'c'; _latin1'B' between _latin1'a' collate latin1_bin and _latin1'c' 0 select _latin1'B' between _latin1'a' and _latin1'c' collate latin1_bin; _latin1'B' between _latin1'a' and _latin1'c' collate latin1_bin 0 select _latin2'B' between _latin1'a' and _latin1'b'; ERROR HY000: Illegal mix of collations (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'between' select _latin1'B' between _latin2'a' and _latin1'b'; ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'between' select _latin1'B' between _latin1'a' and _latin2'b'; ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE) for operation 'between' select _latin1'B' collate latin1_general_ci between _latin1'a' collate latin1_bin and _latin1'b'; ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT), (latin1_bin,EXPLICIT), (latin1_swedish_ci,COERCIBLE) for operation 'between' select _latin1'B' in (_latin1'a',_latin1'b'); _latin1'B' in (_latin1'a',_latin1'b') 1 select _latin1'B' collate latin1_bin in (_latin1'a',_latin1'b'); _latin1'B' collate latin1_bin in (_latin1'a',_latin1'b') 0 select _latin1'B' in (_latin1'a' collate latin1_bin,_latin1'b'); _latin1'B' in (_latin1'a' collate latin1_bin,_latin1'b') 0 select _latin1'B' in (_latin1'a',_latin1'b' collate latin1_bin); _latin1'B' in (_latin1'a',_latin1'b' collate latin1_bin) 0 select _latin2'B' in (_latin1'a',_latin1'b'); ERROR HY000: Illegal mix of collations (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation ' IN ' select _latin1'B' in (_latin2'a',_latin1'b'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation ' IN ' select _latin1'B' in (_latin1'a',_latin2'b'); ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE), (latin2_general_ci,COERCIBLE) for operation ' IN ' select _latin1'B' COLLATE latin1_general_ci in (_latin1'a' COLLATE latin1_bin,_latin1'b'); ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT), (latin1_bin,EXPLICIT), (latin1_swedish_ci,COERCIBLE) for operation ' IN ' select _latin1'B' COLLATE latin1_general_ci in (_latin1'a',_latin1'b' COLLATE latin1_bin); ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT), (latin1_swedish_ci,COERCIBLE), (latin1_bin,EXPLICIT) for operation ' IN ' select collation(bin(130)), coercibility(bin(130)); collation(bin(130)) coercibility(bin(130)) latin1_swedish_ci 4 select collation(oct(130)), coercibility(oct(130)); collation(oct(130)) coercibility(oct(130)) latin1_swedish_ci 4 select collation(conv(130,16,10)), coercibility(conv(130,16,10)); collation(conv(130,16,10)) coercibility(conv(130,16,10)) latin1_swedish_ci 4 select collation(hex(130)), coercibility(hex(130)); collation(hex(130)) coercibility(hex(130)) latin1_swedish_ci 4 select collation(char(130)), coercibility(hex(130)); collation(char(130)) coercibility(hex(130)) latin1_swedish_ci 4 select collation(format(130,10)), coercibility(format(130,10)); collation(format(130,10)) coercibility(format(130,10)) latin1_swedish_ci 4 select collation(lcase(_latin2'a')), coercibility(lcase(_latin2'a')); collation(lcase(_latin2'a')) coercibility(lcase(_latin2'a')) latin2_general_ci 4 select collation(ucase(_latin2'a')), coercibility(ucase(_latin2'a')); collation(ucase(_latin2'a')) coercibility(ucase(_latin2'a')) latin2_general_ci 4 select collation(left(_latin2'a',1)), coercibility(left(_latin2'a',1)); collation(left(_latin2'a',1)) coercibility(left(_latin2'a',1)) latin2_general_ci 4 select collation(right(_latin2'a',1)), coercibility(right(_latin2'a',1)); collation(right(_latin2'a',1)) coercibility(right(_latin2'a',1)) latin2_general_ci 4 select collation(substring(_latin2'a',1,1)), coercibility(substring(_latin2'a',1,1)); collation(substring(_latin2'a',1,1)) coercibility(substring(_latin2'a',1,1)) latin2_general_ci 4 select collation(concat(_latin2'a',_latin2'b')), coercibility(concat(_latin2'a',_latin2'b')); collation(concat(_latin2'a',_latin2'b')) coercibility(concat(_latin2'a',_latin2'b')) latin2_general_ci 4 select collation(lpad(_latin2'a',4,_latin2'b')), coercibility(lpad(_latin2'a',4,_latin2'b')); collation(lpad(_latin2'a',4,_latin2'b')) coercibility(lpad(_latin2'a',4,_latin2'b')) latin2_general_ci 4 select collation(rpad(_latin2'a',4,_latin2'b')), coercibility(rpad(_latin2'a',4,_latin2'b')); collation(rpad(_latin2'a',4,_latin2'b')) coercibility(rpad(_latin2'a',4,_latin2'b')) latin2_general_ci 4 select collation(concat_ws(_latin2'a',_latin2'b')), coercibility(concat_ws(_latin2'a',_latin2'b')); collation(concat_ws(_latin2'a',_latin2'b')) coercibility(concat_ws(_latin2'a',_latin2'b')) latin2_general_ci 4 select collation(make_set(255,_latin2'a',_latin2'b',_latin2'c')), coercibility(make_set(255,_latin2'a',_latin2'b',_latin2'c')); collation(make_set(255,_latin2'a',_latin2'b',_latin2'c')) coercibility(make_set(255,_latin2'a',_latin2'b',_latin2'c')) latin2_general_ci 4 select collation(export_set(255,_latin2'y',_latin2'n',_latin2' ')), coercibility(export_set(255,_latin2'y',_latin2'n',_latin2' ')); collation(export_set(255,_latin2'y',_latin2'n',_latin2' ')) coercibility(export_set(255,_latin2'y',_latin2'n',_latin2' ')) latin2_general_ci 4 select collation(trim(_latin2' a ')), coercibility(trim(_latin2' a ')); collation(trim(_latin2' a ')) coercibility(trim(_latin2' a ')) latin2_general_ci 4 select collation(ltrim(_latin2' a ')), coercibility(ltrim(_latin2' a ')); collation(ltrim(_latin2' a ')) coercibility(ltrim(_latin2' a ')) latin2_general_ci 4 select collation(rtrim(_latin2' a ')), coercibility(rtrim(_latin2' a ')); collation(rtrim(_latin2' a ')) coercibility(rtrim(_latin2' a ')) latin2_general_ci 4 select collation(trim(LEADING _latin2' ' FROM _latin2'a')), coercibility(trim(LEADING _latin2'a' FROM _latin2'a')); collation(trim(LEADING _latin2' ' FROM _latin2'a')) coercibility(trim(LEADING _latin2'a' FROM _latin2'a')) latin2_general_ci 4 select collation(trim(TRAILING _latin2' ' FROM _latin2'a')), coercibility(trim(TRAILING _latin2'a' FROM _latin2'a')); collation(trim(TRAILING _latin2' ' FROM _latin2'a')) coercibility(trim(TRAILING _latin2'a' FROM _latin2'a')) latin2_general_ci 4 select collation(trim(BOTH _latin2' ' FROM _latin2'a')), coercibility(trim(BOTH _latin2'a' FROM _latin2'a')); collation(trim(BOTH _latin2' ' FROM _latin2'a')) coercibility(trim(BOTH _latin2'a' FROM _latin2'a')) latin2_general_ci 4 select collation(repeat(_latin2'a',10)), coercibility(repeat(_latin2'a',10)); collation(repeat(_latin2'a',10)) coercibility(repeat(_latin2'a',10)) latin2_general_ci 4 select collation(reverse(_latin2'ab')), coercibility(reverse(_latin2'ab')); collation(reverse(_latin2'ab')) coercibility(reverse(_latin2'ab')) latin2_general_ci 4 select collation(quote(_latin2'ab')), coercibility(quote(_latin2'ab')); collation(quote(_latin2'ab')) coercibility(quote(_latin2'ab')) latin2_general_ci 4 select collation(soundex(_latin2'ab')), coercibility(soundex(_latin2'ab')); collation(soundex(_latin2'ab')) coercibility(soundex(_latin2'ab')) latin2_general_ci 4 select collation(substring(_latin2'ab',1)), coercibility(substring(_latin2'ab',1)); collation(substring(_latin2'ab',1)) coercibility(substring(_latin2'ab',1)) latin2_general_ci 4 select collation(insert(_latin2'abcd',2,3,_latin2'ef')), coercibility(insert(_latin2'abcd',2,3,_latin2'ef')); collation(insert(_latin2'abcd',2,3,_latin2'ef')) coercibility(insert(_latin2'abcd',2,3,_latin2'ef')) latin2_general_ci 4 select collation(replace(_latin2'abcd',_latin2'b',_latin2'B')), coercibility(replace(_latin2'abcd',_latin2'b',_latin2'B')); collation(replace(_latin2'abcd',_latin2'b',_latin2'B')) coercibility(replace(_latin2'abcd',_latin2'b',_latin2'B')) latin2_general_ci 4 select collation(encode('abcd','ab')), coercibility(encode('abcd','ab')); collation(encode('abcd','ab')) coercibility(encode('abcd','ab')) binary 4 create table t1 select bin(130), oct(130), conv(130,16,10), hex(130), char(130), format(130,10), left(_latin2'a',1), right(_latin2'a',1), lcase(_latin2'a'), ucase(_latin2'a'), substring(_latin2'a',1,1), concat(_latin2'a',_latin2'b'), lpad(_latin2'a',4,_latin2'b'), rpad(_latin2'a',4,_latin2'b'), concat_ws(_latin2'a',_latin2'b'), make_set(255,_latin2'a',_latin2'b',_latin2'c'), export_set(255,_latin2'y',_latin2'n',_latin2' '), trim(_latin2' a '), ltrim(_latin2' a '), rtrim(_latin2' a '), trim(LEADING _latin2' ' FROM _latin2' a '), trim(TRAILING _latin2' ' FROM _latin2' a '), trim(BOTH _latin2' ' FROM _latin2' a '), repeat(_latin2'a',10), reverse(_latin2'ab'), quote(_latin2'ab'), soundex(_latin2'ab'), substring(_latin2'ab',1), insert(_latin2'abcd',2,3,_latin2'ef'), replace(_latin2'abcd',_latin2'b',_latin2'B'), encode('abcd','ab') ; Warnings: Warning 1265 Data truncated for column 'format(130,10)' at row 1 show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `bin(130)` char(64) NOT NULL default '', `oct(130)` char(64) NOT NULL default '', `conv(130,16,10)` char(64) NOT NULL default '', `hex(130)` char(6) NOT NULL default '', `char(130)` char(1) NOT NULL default '', `format(130,10)` char(4) NOT NULL default '', `left(_latin2'a',1)` char(1) character set latin2 NOT NULL default '', `right(_latin2'a',1)` char(1) character set latin2 NOT NULL default '', `lcase(_latin2'a')` char(1) character set latin2 NOT NULL default '', `ucase(_latin2'a')` char(1) character set latin2 NOT NULL default '', `substring(_latin2'a',1,1)` char(1) character set latin2 NOT NULL default '', `concat(_latin2'a',_latin2'b')` char(2) character set latin2 NOT NULL default '', `lpad(_latin2'a',4,_latin2'b')` char(4) character set latin2 NOT NULL default '', `rpad(_latin2'a',4,_latin2'b')` char(4) character set latin2 NOT NULL default '', `concat_ws(_latin2'a',_latin2'b')` char(1) character set latin2 NOT NULL default '', `make_set(255,_latin2'a',_latin2'b',_latin2'c')` char(5) character set latin2 NOT NULL default '', `export_set(255,_latin2'y',_latin2'n',_latin2' ')` char(127) character set latin2 NOT NULL default '', `trim(_latin2' a ')` char(3) character set latin2 NOT NULL default '', `ltrim(_latin2' a ')` char(3) character set latin2 NOT NULL default '', `rtrim(_latin2' a ')` char(3) character set latin2 NOT NULL default '', `trim(LEADING _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '', `trim(TRAILING _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '', `trim(BOTH _latin2' ' FROM _latin2' a ')` char(3) character set latin2 NOT NULL default '', `repeat(_latin2'a',10)` char(10) character set latin2 NOT NULL default '', `reverse(_latin2'ab')` char(2) character set latin2 NOT NULL default '', `quote(_latin2'ab')` char(6) character set latin2 NOT NULL default '', `soundex(_latin2'ab')` char(4) character set latin2 NOT NULL default '', `substring(_latin2'ab',1)` char(2) character set latin2 NOT NULL default '', `insert(_latin2'abcd',2,3,_latin2'ef')` char(6) character set latin2 NOT NULL default '', `replace(_latin2'abcd',_latin2'b',_latin2'B')` char(4) character set latin2 NOT NULL default '', `encode('abcd','ab')` binary(4) NOT NULL default '' ) ENGINE=MyISAM DEFAULT CHARSET=latin1 drop table t1; create table t1 (a char character set latin2); insert into t1 values (null); select charset(a), collation(a), coercibility(a) from t1; charset(a) collation(a) coercibility(a) latin2 latin2_general_ci 2 drop table t1; select charset(null), collation(null), coercibility(null); charset(null) collation(null) coercibility(null) binary binary 5 CREATE TABLE t1 (a int, b int); CREATE TABLE t2 (a int, b int); INSERT INTO t1 VALUES (1,1),(2,2); INSERT INTO t2 VALUES (2,2),(3,3); select t1.*,t2.* from t1 left join t2 on (t1.b=t2.b) where collation(t2.a) = _utf8'binary' order by t1.a,t2.a; a b a b 1 1 NULL NULL 2 2 2 2 select t1.*,t2.* from t1 left join t2 on (t1.b=t2.b) where charset(t2.a) = _utf8'binary' order by t1.a,t2.a; a b a b 1 1 NULL NULL 2 2 2 2 select t1.*,t2.* from t1 left join t2 on (t1.b=t2.b) where coercibility(t2.a) = 2 order by t1.a,t2.a; a b a b 1 1 NULL NULL 2 2 2 2 DROP TABLE t1, t2; select SUBSTR('abcdefg',3,2); SUBSTR('abcdefg',3,2) cd select SUBSTRING('abcdefg',3,2); SUBSTRING('abcdefg',3,2) cd select SUBSTR('abcdefg',-3,2) FROM DUAL; SUBSTR('abcdefg',-3,2) ef select SUBSTR('abcdefg',-1,5) FROM DUAL; SUBSTR('abcdefg',-1,5) g select SUBSTR('abcdefg',0,0) FROM DUAL; SUBSTR('abcdefg',0,0) select SUBSTR('abcdefg',-1,-1) FROM DUAL; SUBSTR('abcdefg',-1,-1) select SUBSTR('abcdefg',1,-1) FROM DUAL; SUBSTR('abcdefg',1,-1) create table t7 (s1 char); select * from t7 where concat(s1 collate latin1_general_ci,s1 collate latin1_swedish_ci) = 'AA'; ERROR HY000: Illegal mix of collations (latin1_general_ci,EXPLICIT) and (latin1_swedish_ci,EXPLICIT) for operation 'concat' drop table t7; select substring_index("1abcd;2abcd;3abcd;4abcd", ';', 2),substring_index("1abcd;2abcd;3abcd;4abcd", ';', -2); substring_index("1abcd;2abcd;3abcd;4abcd", ';', 2) substring_index("1abcd;2abcd;3abcd;4abcd", ';', -2) 1abcd;2abcd 3abcd;4abcd explain extended select md5('hello'), sha('abc'), sha1('abc'), soundex(''), 'mood' sounds like 'mud', aes_decrypt(aes_encrypt('abc','1'),'1'),concat('*',space(5),'*'), reverse('abc'), rpad('a',4,'1'), lpad('a',4,'1'), concat_ws(',','',NULL,'a'),make_set(255,_latin2'a',_latin2'b',_latin2'c'),elt(2,1),locate("a","b",2),format(130,10),char(0),conv(130,16,10),hex(130),binary 'HE', export_set(255,_latin2'y',_latin2'n',_latin2' '),FIELD('b' COLLATE latin1_bin,'A','B'),FIND_IN_SET(_latin1'B',_latin1'a,b,c,d'),collation(conv(130,16,10)), coercibility(conv(130,16,10)),length('\n\t\r\b\0\_\%\\'),bit_length('\n\t\r\b\0\_\%\\'),bit_length('\n\t\r\b\0\_\%\\'),concat('monty',' was here ','again'),length('hello'),char(ascii('h')),ord('h'),quote(1/0),crc32("123"),replace('aaaa','a','b'),insert('txs',2,1,'hi'),left(_latin2'a',1),right(_latin2'a',1),lcase(_latin2'a'),ucase(_latin2'a'),SUBSTR('abcdefg',3,2),substring_index("1abcd;2abcd;3abcd;4abcd", ';', 2),trim(_latin2' a '),ltrim(_latin2' a '),rtrim(_latin2' a '), decode(encode(repeat("a",100000),"monty"),"monty"); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE NULL NULL NULL NULL NULL NULL NULL No tables used Warnings: Note 1003 select md5(_latin1'hello') AS `md5('hello')`,sha(_latin1'abc') AS `sha('abc')`,sha(_latin1'abc') AS `sha1('abc')`,soundex(_latin1'') AS `soundex('')`,(soundex(_latin1'mood') = soundex(_latin1'mud')) AS `'mood' sounds like 'mud'`,aes_decrypt(aes_encrypt(_latin1'abc',_latin1'1'),_latin1'1') AS `aes_decrypt(aes_encrypt('abc','1'),'1')`,concat(_latin1'*',repeat(_latin1' ',5),_latin1'*') AS `concat('*',space(5),'*')`,reverse(_latin1'abc') AS `reverse('abc')`,rpad(_latin1'a',4,_latin1'1') AS `rpad('a',4,'1')`,lpad(_latin1'a',4,_latin1'1') AS `lpad('a',4,'1')`,concat_ws(_latin1',',_latin1'',NULL,_latin1'a') AS `concat_ws(',','',NULL,'a')`,make_set(255,_latin2'a',_latin2'b',_latin2'c') AS `make_set(255,_latin2'a',_latin2'b',_latin2'c')`,elt(2,1) AS `elt(2,1)`,locate(_latin1'a',_latin1'b',2) AS `locate("a","b",2)`,format(130,10) AS `format(130,10)`,char(0) AS `char(0)`,conv(130,16,10) AS `conv(130,16,10)`,hex(130) AS `hex(130)`,cast(_latin1'HE' as char charset binary) AS `binary 'HE'`,export_set(255,_latin2'y',_latin2'n',_latin2' ') AS `export_set(255,_latin2'y',_latin2'n',_latin2' ')`,field((_latin1'b' collate _latin1'latin1_bin'),_latin1'A',_latin1'B') AS `FIELD('b' COLLATE latin1_bin,'A','B')`,find_in_set(_latin1'B',_latin1'a,b,c,d') AS `FIND_IN_SET(_latin1'B',_latin1'a,b,c,d')`,collation(conv(130,16,10)) AS `collation(conv(130,16,10))`,coercibility(conv(130,16,10)) AS `coercibility(conv(130,16,10))`,length(_latin1'\n \r\0\\_\\%\\') AS `length('\n\t\r\b\0\_\%\\')`,bit_length(_latin1'\n \r\0\\_\\%\\') AS `bit_length('\n\t\r\b\0\_\%\\')`,bit_length(_latin1'\n \r\0\\_\\%\\') AS `bit_length('\n\t\r\b\0\_\%\\')`,concat(_latin1'monty',_latin1' was here ',_latin1'again') AS `concat('monty',' was here ','again')`,length(_latin1'hello') AS `length('hello')`,char(ascii(_latin1'h')) AS `char(ascii('h'))`,ord(_latin1'h') AS `ord('h')`,quote((1 / 0)) AS `quote(1/0)`,crc32(_latin1'123') AS `crc32("123")`,replace(_latin1'aaaa',_latin1'a',_latin1'b') AS `replace('aaaa','a','b')`,insert(_latin1'txs',2,1,_latin1'hi') AS `insert('txs',2,1,'hi')`,left(_latin2'a',1) AS `left(_latin2'a',1)`,right(_latin2'a',1) AS `right(_latin2'a',1)`,lcase(_latin2'a') AS `lcase(_latin2'a')`,ucase(_latin2'a') AS `ucase(_latin2'a')`,substr(_latin1'abcdefg',3,2) AS `SUBSTR('abcdefg',3,2)`,substr_index(_latin1'1abcd;2abcd;3abcd;4abcd',_latin1';',2) AS `substring_index("1abcd;2abcd;3abcd;4abcd", ';', 2)`,trim(_latin2' a ') AS `trim(_latin2' a ')`,ltrim(_latin2' a ') AS `ltrim(_latin2' a ')`,rtrim(_latin2' a ') AS `rtrim(_latin2' a ')`,decode(encode(repeat(_latin1'a',100000))) AS `decode(encode(repeat("a",100000),"monty"),"monty")` SELECT lpad(12345, 5, "#"); lpad(12345, 5, "#") 12345 SELECT conv(71, 10, 36), conv('1Z', 36, 10); conv(71, 10, 36) conv('1Z', 36, 10) 1Z 71 create table t1 (id int(1), str varchar(10)) DEFAULT CHARSET=utf8; insert into t1 values (1,'aaaaaaaaaa'), (2,'bbbbbbbbbb'); create table t2 (id int(1), str varchar(10)) DEFAULT CHARSET=utf8; insert into t2 values (1,'cccccccccc'), (2,'dddddddddd'); select substring(concat(t1.str, t2.str), 1, 15) "name" from t1, t2 where t2.id=t1.id order by name; name aaaaaaaaaaccccc bbbbbbbbbbddddd drop table t1, t2; create table t1 (c1 INT, c2 INT UNSIGNED); insert into t1 values ('21474836461','21474836461'); Warnings: Warning 1265 Data truncated for column 'c1' at row 1 Warning 1265 Data truncated for column 'c2' at row 1 insert into t1 values ('-21474836461','-21474836461'); Warnings: Warning 1265 Data truncated for column 'c1' at row 1 Warning 1265 Data truncated for column 'c2' at row 1 show warnings; Level Code Message Warning 1265 Data truncated for column 'c1' at row 1 Warning 1265 Data truncated for column 'c2' at row 1 select * from t1; c1 c2 2147483647 4294967295 -2147483648 0 drop table t1; select left(1234, 3) + 0; left(1234, 3) + 0 123 create table t1 (a int not null primary key, b varchar(40), c datetime); insert into t1 (a,b,c) values (1,'Tom','2004-12-10 12:13:14'),(2,'ball games','2004-12-10 12:13:14'), (3,'Basil','2004-12-10 12:13:14'), (4,'Dean','2004-12-10 12:13:14'),(5,'Ellis','2004-12-10 12:13:14'), (6,'Serg','2004-12-10 12:13:14'), (7,'Sergei','2004-12-10 12:13:14'),(8,'Georg','2004-12-10 12:13:14'),(9,'Salle','2004-12-10 12:13:14'),(10,'Sinisa','2004-12-10 12:13:14'); select count(*) as total, left(c,10) as reg from t1 group by reg order by reg desc limit 0,12; total reg 10 2004-12-10 drop table t1; select trim(null from 'kate') as "must_be_null"; must_be_null NULL select trim('xyz' from null) as "must_be_null"; must_be_null NULL CREATE TABLE t1 ( id int(11) NOT NULL auto_increment, a bigint(20) unsigned default NULL, PRIMARY KEY (id) ) ENGINE=MyISAM; INSERT INTO t1 VALUES ('0','16307858876001849059'); SELECT CONV('e251273eb74a8ee3', 16, 10); CONV('e251273eb74a8ee3', 16, 10) 16307858876001849059 EXPLAIN SELECT id FROM t1 WHERE a = 16307858876001849059; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 EXPLAIN SELECT id FROM t1 WHERE a = CONV('e251273eb74a8ee3', 16, 10); id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE t1 system NULL NULL NULL NULL 1 DROP TABLE t1; SELECT CHAR(NULL,121,83,81,'76') as my_column; my_column ySQL SELECT CHAR_LENGTH(CHAR(NULL,121,83,81,'76')) as my_column; my_column 4 CREATE TABLE t1 (id int PRIMARY KEY, str char(255) NOT NULL); CREATE TABLE t2 (id int NOT NULL UNIQUE); INSERT INTO t2 VALUES (1),(2); INSERT INTO t1 VALUES (1, aes_encrypt('foo', 'bar')); INSERT INTO t1 VALUES (2, 'not valid'); SELECT t1.id, aes_decrypt(str, 'bar') FROM t1, t2 WHERE t1.id = t2.id; id aes_decrypt(str, 'bar') 1 foo 2 NULL SELECT t1.id, aes_decrypt(str, 'bar') FROM t1, t2 WHERE t1.id = t2.id ORDER BY t1.id; id aes_decrypt(str, 'bar') 1 foo 2 NULL DROP TABLE t1, t2; select field(0,NULL,1,0), field("",NULL,"bar",""), field(0.0,NULL,1.0,0.0); field(0,NULL,1,0) field("",NULL,"bar","") field(0.0,NULL,1.0,0.0) 3 3 3 select field(NULL,1,2,NULL), field(NULL,1,2,0); field(NULL,1,2,NULL) field(NULL,1,2,0) 0 0 CREATE TABLE t1 (str varchar(20) PRIMARY KEY); CREATE TABLE t2 (num int primary key); INSERT INTO t1 VALUES ('notnumber'); INSERT INTO t2 VALUES (0), (1); SELECT * FROM t1, t2 WHERE num=str; str num notnumber 0 SELECT * FROM t1, t2 WHERE num=substring(str from 1 for 6); str num notnumber 0 DROP TABLE t1,t2; CREATE TABLE t1( id int(11) NOT NULL auto_increment, pc int(11) NOT NULL default '0', title varchar(20) default NULL, PRIMARY KEY (id) ); INSERT INTO t1 VALUES (1, 0, 'Main'), (2, 1, 'Toys'), (3, 1, 'Games'); SELECT t1.id, CONCAT_WS('->', t3.title, t2.title, t1.title) as col1 FROM t1 LEFT JOIN t1 AS t2 ON t1.pc=t2.id LEFT JOIN t1 AS t3 ON t2.pc=t3.id; id col1 1 Main 2 Main->Toys 3 Main->Games SELECT t1.id, CONCAT_WS('->', t3.title, t2.title, t1.title) as col1 FROM t1 LEFT JOIN t1 AS t2 ON t1.pc=t2.id LEFT JOIN t1 AS t3 ON t2.pc=t3.id WHERE CONCAT_WS('->', t3.title, t2.title, t1.title) LIKE '%Toys%'; id col1 2 Main->Toys DROP TABLE t1; CREATE TABLE t1( trackid int(10) unsigned NOT NULL auto_increment, trackname varchar(100) NOT NULL default '', PRIMARY KEY (trackid) ); CREATE TABLE t2( artistid int(10) unsigned NOT NULL auto_increment, artistname varchar(100) NOT NULL default '', PRIMARY KEY (artistid) ); CREATE TABLE t3( trackid int(10) unsigned NOT NULL, artistid int(10) unsigned NOT NULL, PRIMARY KEY (trackid,artistid) ); INSERT INTO t1 VALUES (1, 'April In Paris'), (2, 'Autumn In New York'); INSERT INTO t2 VALUES (1, 'Vernon Duke'); INSERT INTO t3 VALUES (1,1); SELECT CONCAT_WS(' ', trackname, artistname) trackname, artistname FROM t1 LEFT JOIN t3 ON t1.trackid=t3.trackid LEFT JOIN t2 ON t2.artistid=t3.artistid WHERE CONCAT_WS(' ', trackname, artistname) LIKE '%In%'; trackname artistname April In Paris Vernon Duke Vernon Duke Autumn In New York NULL DROP TABLE t1,t2,t3; create table t1 (b varchar(5)); insert t1 values ('ab'), ('abc'), ('abcd'), ('abcde'); select *,substring(b,1),substring(b,-1),substring(b,-2),substring(b,-3),substring(b,-4),substring(b,-5) from t1; b substring(b,1) substring(b,-1) substring(b,-2) substring(b,-3) substring(b,-4) substring(b,-5) ab ab b ab abc abc c bc abc abcd abcd d cd bcd abcd abcde abcde e de cde bcde abcde select * from (select *,substring(b,1),substring(b,-1),substring(b,-2),substring(b,-3),substring(b,-4),substring(b,-5) from t1) t; b substring(b,1) substring(b,-1) substring(b,-2) substring(b,-3) substring(b,-4) substring(b,-5) ab ab b ab abc abc c bc abc abcd abcd d cd bcd abcd abcde abcde e de cde bcde abcde drop table t1; select hex(29223372036854775809), hex(-29223372036854775809); hex(29223372036854775809) hex(-29223372036854775809) FFFFFFFFFFFFFFFF FFFFFFFFFFFFFFFF