drop table if exists t1; select (1,2,3) IN ((3,2,3), (1,2,3), (1,3,3)); (1,2,3) IN ((3,2,3), (1,2,3), (1,3,3)) 1 select row(10,2,3) IN (row(3,2,3), row(1,2,3), row(1,3,3)); row(10,2,3) IN (row(3,2,3), row(1,2,3), row(1,3,3)) 0 select row(1,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3)); row(1,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3)) 1 select row(10,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3)); row(10,2,3) IN (row(3,NULL,3), row(1,2,3), row(1,3,3)) 0 select row('a',1.5,3) IN (row(1,2,3), row('a',1.5,3), row('a','a','a')); row('a',1.5,3) IN (row(1,2,3), row('a',1.5,3), row('a','a','a')) 1 select row('a',0,3) IN (row(3,2,3), row('a','0','3'), row(1,3,3)); row('a',0,3) IN (row(3,2,3), row('a','0','3'), row(1,3,3)) 1 select row('a',0,3) IN (row(3,2,3), row('a','a','3'), row(1,3,3)); row('a',0,3) IN (row(3,2,3), row('a','a','3'), row(1,3,3)) 1 select row('a',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3)); row('a',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3)) 1 select row('b',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3)); row('b',1.5,3) IN (row(3,NULL,3), row('a',1.5,3), row(1,3,3)) 0 select row('b',1.5,3) IN (row('b',NULL,3), row('a',1.5,3), row(1,3,3)); row('b',1.5,3) IN (row('b',NULL,3), row('a',1.5,3), row(1,3,3)) NULL select row('b',1.5,3) IN (row('b',NULL,4), row('a',1.5,3), row(1,3,3)); row('b',1.5,3) IN (row('b',NULL,4), row('a',1.5,3), row(1,3,3)) 0 select (1,2,(3,4)) IN ((3,2,(3,4)), (1,2,(3,4))); (1,2,(3,4)) IN ((3,2,(3,4)), (1,2,(3,4))) 1 select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,4)); ERROR 21000: Operand should contain 2 column(s) select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL))); row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL))) NULL explain extended select row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL))); 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 ((1,2,(3,4)) in ((3,2,(3,4)),(1,2,(3,NULL)))) AS `row(1,2,row(3,4)) IN (row(3,2,row(3,4)), row(1,2,row(3,NULL)))` SELECT (1,2,3)=(0,NULL,3); (1,2,3)=(0,NULL,3) 0 SELECT (1,2,3)=(1,NULL,3); (1,2,3)=(1,NULL,3) NULL SELECT (1,2,3)=(1,NULL,0); (1,2,3)=(1,NULL,0) NULL SELECT ROW(1,2,3)=ROW(1,2,3); ROW(1,2,3)=ROW(1,2,3) 1 SELECT ROW(2,2,3)=ROW(1+1,2,3); ROW(2,2,3)=ROW(1+1,2,3) 1 SELECT ROW(1,2,3)=ROW(1+1,2,3); ROW(1,2,3)=ROW(1+1,2,3) 0 SELECT ROW(1,2,3)ROW(1+1,2,3); ROW(1,2,3)>ROW(1+1,2,3) 0 SELECT ROW(1,2,3)<=ROW(1+1,2,3); ROW(1,2,3)<=ROW(1+1,2,3) 1 SELECT ROW(1,2,3)>=ROW(1+1,2,3); ROW(1,2,3)>=ROW(1+1,2,3) 0 SELECT ROW(1,2,3)<>ROW(1+1,2,3); ROW(1,2,3)<>ROW(1+1,2,3) 1 SELECT ROW(NULL,2,3)=ROW(NULL,2,3); ROW(NULL,2,3)=ROW(NULL,2,3) NULL SELECT ROW(NULL,2,3)<=>ROW(NULL,2,3); ROW(NULL,2,3)<=>ROW(NULL,2,3) 1 SELECT ROW(1,2,ROW(3,4,5))=ROW(1,2,ROW(3,4,5)); ROW(1,2,ROW(3,4,5))=ROW(1,2,ROW(3,4,5)) 1 SELECT ROW('test',2,3.33)=ROW('test',2,3.33); ROW('test',2,3.33)=ROW('test',2,3.33) 1 SELECT ROW('test',2,3.33)=ROW('test',2,3.33,4); ERROR 21000: Operand should contain 3 column(s) SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,33)); ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,33)) 1 SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,3)); ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,3)) 0 SELECT ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,NULL)); ROW('test',2,ROW(3,33))=ROW('test',2,ROW(3,NULL)) NULL SELECT ROW('test',2,ROW(3,33))=ROW('test',2,4); ERROR 21000: Operand should contain 2 column(s) create table t1 ( a int, b int, c int); insert into t1 values (1,2,3), (2,3,1), (3,2,1), (1,2,NULL); select * from t1 where ROW(1,2,3)=ROW(a,b,c); a b c 1 2 3 select * from t1 where ROW(0,2,3)=ROW(a,b,c); a b c select * from t1 where ROW(1,2,3) ROW(3,4); ROW(2,10) <=> ROW(3,4) 0 SELECT ROW(NULL,10) <=> ROW(3,NULL); ROW(NULL,10) <=> ROW(3,NULL) 0