MySQL数据库

开发平台：

Visual C++

func_equal.test：源码内容

							# Initialise
--disable_warnings
drop table if exists t1,t2;
--enable_warnings
#
# Testing of the <=> operator
#
#
# First some simple tests
#
select 0<=>0,0.0<=>0.0,"A"<=>"A",NULL<=>NULL;
select 1<=>0,0<=>NULL,NULL<=>0;
select 1.0<=>0.0,0.0<=>NULL,NULL<=>0.0;
select "A"<=>"B","A"<=>NULL,NULL<=>"A";
#
# Test with tables
#
create table t1 (id int, value int);
create table t2 (id int, value int);
insert into t1 values (1,null);
insert into t2 values (1,null);
select t1.*, t2.*, t1.value<=>t2.value from t1, t2 where t1.id=t2.id and t1.id=1;
select * from t1 where id <=>id;
select * from t1 where value <=> value;
select * from t1 where id <=> value or value<=>id;
drop table t1,t2;
# End of 4.1 tests

						