drop table if exists t1;
drop database if exists mysqltest;
CREATE TABLE t1 (a INT, b INT, c INT, d INT);
INSERT INTO t1 VALUES (1,3,0,NULL),(2,2,0,NULL),(3,4,0,NULL),(4,2,0,NULL);
SELECT * FROM t1;
a	b	c	d
1	3	0	NULL
2	2	0	NULL
3	4	0	NULL
4	2	0	NULL
UPDATE t1 SET c=LAST_VALUE(@last_a:=a,@last_b:=b,@last_c:=c,1), d=4211 WHERE c=0 ORDER BY b DESC LIMIT 1;
SELECT @last_a, @last_b, @last_c;
@last_a	@last_b	@last_c
3	4	0
SELECT * FROM t1;
a	b	c	d
1	3	0	NULL
2	2	0	NULL
3	4	1	4211
4	2	0	NULL
DROP TABLE t1;
SELECT LAST_VALUE(@last_a:=1,@last_b:=1);
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					LAST_VALUE(@last_a:=1,@last_b:=1)	3	1	1	N	32897	0	63
LAST_VALUE(@last_a:=1,@last_b:=1)
1
select @last_b;
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					@last_b	8	20	1	Y	32896	0	63
@last_b
1
SELECT LAST_VALUE(@last_a:=1,@last_b:=1.0);
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					LAST_VALUE(@last_a:=1,@last_b:=1.0)	246	4	3	N	32897	1	63
LAST_VALUE(@last_a:=1,@last_b:=1.0)
1.0
select @last_b;
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					@last_b	246	83	3	Y	32896	38	63
@last_b
1.0
SELECT LAST_VALUE(@last_a:=1,@last_b:="hello");
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					LAST_VALUE(@last_a:=1,@last_b:="hello")	253	5	5	N	1	39	8
LAST_VALUE(@last_a:=1,@last_b:="hello")
hello
select @last_b;
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					@last_b	251	16777215	5	Y	0	39	8
@last_b
hello
SELECT date(LAST_VALUE(@last_a:=1,@last_b:="2001-02-03"));
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					date(LAST_VALUE(@last_a:=1,@last_b:="2001-02-03"))	10	10	10	Y	128	0	63
date(LAST_VALUE(@last_a:=1,@last_b:="2001-02-03"))
2001-02-03
select @last_b;
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					@last_b	251	16777215	10	Y	0	39	8
@last_b
2001-02-03
SELECT LAST_VALUE(@last_a:=1,@last_b:="2001-02-03",NULL);
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					LAST_VALUE(@last_a:=1,@last_b:="2001-02-03",NULL)	6	0	0	Y	32896	0	63
LAST_VALUE(@last_a:=1,@last_b:="2001-02-03",NULL)
NULL
select @last_b;
Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
def					@last_b	251	16777215	10	Y	0	39	8
@last_b
2001-02-03
SELECT LAST_VALUE();
ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ')' at line 1