#
# test variables
#
drop table if exists t1;
set @`test`=1,@TEST=3,@select=2,@t5=1.23456;
select @test,@`select`,@TEST,@not_used;
set @test_int=10,@test_double=1e-10,@test_string="abcdeghi",@test_string2="abcdefghij",@select=NULL;
select @test_int,@test_double,@test_string,@test_string2,@select;
set @test_int="hello",@test_double="hello",@test_string="hello",@test_string2="hello";
select @test_int,@test_double,@test_string,@test_string2;
set @test_int="hellohello",@test_double="hellohello",@test_string="hellohello",@test_string2="hellohello";
select @test_int,@test_double,@test_string,@test_string2;
set @test_int=null,@test_double=null,@test_string=null,@test_string2=null;
select @test_int,@test_double,@test_string,@test_string2;
select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;
select @t5;

#
# Test problem with WHERE and variables
#

CREATE TABLE t1 (c_id INT(4) NOT NULL, c_name CHAR(20), c_country CHAR(3), PRIMARY KEY(c_id));
INSERT INTO t1 VALUES (1,'Bozo','USA'),(2,'Ronald','USA'),(3,'Kinko','IRE'),(4,'Mr. Floppy','GB');
SELECT @min_cid:=min(c_id), @max_cid:=max(c_id) from t1;
SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid;
SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid OR c_id=666;
ALTER TABLE t1 DROP PRIMARY KEY;
select * from t1 where c_id=@min_cid OR c_id=@max_cid;
drop table t1;

#
# Test system variables
#

select @@VERSION=version();
select last_insert_id(345);
select @@IDENTITY,last_insert_id();
select @@identity;
--error 1193
select @@unknown_variable;