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USE test;
#
# MDEV-14013 : sql_mode=EMPTY_STRING_IS_NULL
#
set @mode='ORACLE,EMPTY_STRING_IS_NULL';
SET SESSION character_set_connection=latin2;
SET SESSION character_set_client=cp1250;
#
# Test litteral
#
SET sql_mode=@mode;
select @@sql_mode;
@@sql_mode
PIPES_AS_CONCAT,ANSI_QUOTES,IGNORE_SPACE,ORACLE,NO_KEY_OPTIONS,NO_TABLE_OPTIONS,NO_FIELD_OPTIONS,NO_AUTO_CREATE_USER,EMPTY_STRING_IS_NULL,SIMULTANEOUS_ASSIGNMENT
SELECT '',CHARSET(''), null, CHARSET(null), CAST(null as char(10)), CHARSET(CAST(null as char(10))), 'x', CHARSET('x');
NULL CHARSET('') NULL CHARSET(null) CAST(null as char(10)) CHARSET(CAST(null as char(10))) x CHARSET('x')
NULL latin2 NULL binary NULL latin2 x latin2
SELECT CHARSET(NULLIF('','')),NULLIF('','');
CHARSET(NULLIF('','')) NULLIF('','')
latin2 NULL
SET sql_mode=default;
SELECT '',CHARSET(''), null, CHARSET(null), CAST(null as char(10)), CHARSET(CAST(null as char(10))), 'x', CHARSET('x');
CHARSET('') NULL CHARSET(null) CAST(null as char(10)) CHARSET(CAST(null as char(10))) x CHARSET('x')
latin2 NULL binary NULL latin2 x latin2
SELECT CHARSET(NULLIF('','')),NULLIF('','');
CHARSET(NULLIF('','')) NULLIF('','')
latin2 NULL
#
# Test NCHAR litteral
#
SET sql_mode=@mode;
SELECT N'',CHARSET(N''), N'x', CHARSET(N'x');
NULL CHARSET(N'') x CHARSET(N'x')
NULL utf8mb3 x utf8mb3
SELECT CHARSET(NULLIF(N'',N'')),NULLIF(N'',N'');
CHARSET(NULLIF(N'',N'')) NULLIF(N'',N'')
utf8mb3 NULL
SET sql_mode=default;
SELECT N'',CHARSET(N''), N'x', CHARSET(N'x');
CHARSET(N'') x CHARSET(N'x')
utf8mb3 x utf8mb3
SELECT CHARSET(NULLIF(N'',N'')),NULLIF(N'',N'');
CHARSET(NULLIF(N'',N'')) NULLIF(N'',N'')
utf8mb3 NULL
#
# Test CHARSET prefix litteral
#
SET sql_mode=@mode;
SELECT _cp1250 '',CHARSET(_cp1250 ''), _cp1250 'x', CHARSET(_cp1250 'x');
NULL CHARSET(_cp1250 '') x CHARSET(_cp1250 'x')
NULL cp1250 x cp1250
SELECT CHARSET(NULLIF(_cp1250 '',_cp1250 '')),NULLIF(_cp1250 '',_cp1250 '');
CHARSET(NULLIF(_cp1250 '',_cp1250 '')) NULLIF(_cp1250 '',_cp1250 '')
cp1250 NULL
SET sql_mode=default;
SELECT _cp1250 '',CHARSET(_cp1250 ''), _cp1250 'x', CHARSET(_cp1250 'x');
CHARSET(_cp1250 '') x CHARSET(_cp1250 'x')
cp1250 x cp1250
SELECT CHARSET(NULLIF(_cp1250 '',_cp1250 '')),NULLIF(_cp1250 '',_cp1250 '');
CHARSET(NULLIF(_cp1250 '',_cp1250 '')) NULLIF(_cp1250 '',_cp1250 '')
cp1250 NULL
SET sql_mode=@mode;
#
# Test litteral concat
#
SELECT 'a' 'b';
ab
ab
SELECT 'a' '';
a
a
SELECT '' 'b';
b
b
SELECT '' '';
NULL
NULL
SELECT '' 'b' 'c';
bc
bc
SELECT '' '' 'c';
c
c
SELECT 'a' '' 'c';
ac
ac
SELECT 'a' '' '';
a
a
SELECT '' '' '';
NULL
NULL
SELECT '' '' '',CHARSET('' '' '');
NULL CHARSET('' '' '')
NULL latin2
SELECT _latin1'' '' '',CHARSET(_latin1'' '' '');
NULL CHARSET(_latin1'' '' '')
NULL latin1
SELECT N'' '' '',CHARSET(N'' '' '');
NULL CHARSET(N'' '' '')
NULL utf8mb3
#
# UNION - implicit group by
#
SELECT 1, null
UNION
SELECT 1 , ''
ORDER BY 1;
1 NULL
1 NULL
SELECT 1, null
UNION
SELECT 1 , N''
ORDER BY 1;
1 NULL
1 NULL
SELECT 1, null
UNION
SELECT 1 , _cp1250 ''
ORDER BY 1;
1 NULL
1 NULL
SELECT NULLIF(_cp1250 '',_cp1250 '')
UNION
SELECT NULLIF(N'',N'');
NULLIF(_cp1250 '',_cp1250 '')
NULL
SELECT 1 , _latin2 ''
UNION
SELECT 1 , _cp1250 '';
ERROR HY000: Illegal mix of collations (latin2_general_ci,IGNORABLE) and (cp1250_general_ci,IGNORABLE) for operation 'UNION'
SELECT 1, null
UNION
SELECT 1 , ''
UNION
SELECT 1 , N'';
1 NULL
1 NULL
CREATE TABLE t1 (c1 INT,c2 VARCHAR(10));
INSERT INTO t1 VALUES (1,'one');
INSERT INTO t1 VALUES (1,'');
INSERT INTO t1 VALUES (1,null);
#
# Test in a view
#
CREATE VIEW v1
AS SELECT c1, c2
FROM t1
UNION
SELECT c1 , ''
FROM t1
ORDER BY 1,2;
SELECT * FROM v1;
c1 c2
1 NULL
1 one
SHOW CREATE VIEW v1;
View Create View character_set_client collation_connection
v1 CREATE VIEW "v1" AS select "t1"."c1" AS "c1","t1"."c2" AS "c2" from "t1" union select "t1"."c1" AS "c1",NULL AS "NULL" from "t1" order by 1,2 cp1250 latin2_general_ci
DROP VIEW v1;
DROP TABLE t1;
EXPLAIN EXTENDED SELECT '';
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select NULL AS "NULL"
EXPLAIN EXTENDED SELECT _latin1'';
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select NULL AS "NULL"
EXPLAIN EXTENDED SELECT N'';
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select NULL AS "NULL"
EXPLAIN EXTENDED SELECT '' '';
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select NULL AS "NULL"
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