Hello there, hope in your help.
I tried this query update and I’ve this error:
[Err] 1111 - Invalid use of group function
Please tell me how to resolve this problem … thank you.
[SQL] UPDATE tbl_A A
JOIN tbl_CC CC ON A.idticket = CC.idticket
SET A.FieldUpdate =
(
TIME_TO_SEC(
TIMEDIFF(
STR_TO_DATE(
MAX(CC.myDate),
'%d/%m/%Y %H:%i:%s'
),
STR_TO_DATE(
MIN(CC.myDate),
'%d/%m/%Y %H:%i:%s'
)
)
) / 60
);
I tried this new solution, but I don’t understand why the query update all rows, of the field DAZ,and not only the row call to JOIN: 
mysql> UPDATE tbl_1 t1,
(
SELECT
idticket,
TIME_TO_SEC(
TIMEDIFF(
TRIM(
STR_TO_DATE(
MAX(Date_hour),
'%d/%m/%Y %H:%i'
)
),
TRIM(
STR_TO_DATE(
MIN(Date_hour),
'%d/%m/%Y %H:%i'
)
)
)
) / 60 AS selected_value
FROM
tbl_2
) AS t2
JOIN tbl_1 ON tbl_1.idticket = t2.idticket
SET t1.DAZ = t2.selected_value;
SELECT
*
FROM
tbl_1;
Query OK, 10 rows affected
Rows matched: 10 Changed: 10 Warnings: 0
+-----+----------+----+
| DAZ | idticket | ID |
+-----+----------+----+
| 4 | 36237886 | 1 |
| 4 | 36237887 | 2 |
| 4 | 36237888 | 3 |
| 4 | 36237889 | 4 |
| 4 | 36237890 | 5 |
| 4 | 36237891 | 6 |
| 4 | 36237892 | 7 |
| 4 | 36237893 | 8 |
| 4 | 36237894 | 9 |
| 4 | 36237895 | 10 |
+-----+----------+----+
10 rows in set
the tables:
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for `tbl_2`
-- ----------------------------
DROP TABLE IF EXISTS `tbl_2`;
CREATE TABLE `tbl_2` (
`idticket` varchar(255) DEFAULT NULL,
`Date_hour` varchar(255) DEFAULT NULL,
`id` int(10) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1;
-- ----------------------------
-- Records of tbl_2
-- ----------------------------
INSERT INTO `tbl_2` VALUES ('36237886', '06/02/2013 15:26', '1');
INSERT INTO `tbl_2` VALUES ('36237886', '06/02/2013 15:30', '2');
-- ----------------------------
-- Table structure for `tbl_1`
-- ----------------------------
DROP TABLE IF EXISTS `tbl_1`;
CREATE TABLE `tbl_1` (
`DAZ` varchar(255) DEFAULT NULL,
`idticket` varchar(255) DEFAULT NULL,
`ID` int(10) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=latin1;
-- ----------------------------
-- Records of tbl_1
-- ----------------------------
INSERT INTO `tbl_1` VALUES ('', '36237886', '1');
INSERT INTO `tbl_1` VALUES ('', '36237887', '2');
INSERT INTO `tbl_1` VALUES ('', '36237888', '3');
INSERT INTO `tbl_1` VALUES ('', '36237889', '4');
INSERT INTO `tbl_1` VALUES ('', '36237890', '5');
INSERT INTO `tbl_1` VALUES ('', '36237891', '6');
INSERT INTO `tbl_1` VALUES ('', '36237892', '7');
INSERT INTO `tbl_1` VALUES ('', '36237893', '8');
INSERT INTO `tbl_1` VALUES ('', '36237894', '9');
INSERT INTO `tbl_1` VALUES ('', '36237895', '10');
once again, it looks like you are making things way too hard on yourself
to begin with, you should define your datetime columns as DATETIME, not as VARCHAR(255)
sheesh :mad:
if you can make that change, you will find that many of your sql problems simply go away
Not lose your patience with me please 
I’ve changed my datetime columns as DATETIME.
I tried this version but the query updates all rows of the field DAZ and not only the row to join…
mysql> UPDATE tbl_1 t1,
(
SELECT
idticket,
TIME_TO_SEC(
TIMEDIFF(
TRIM(MAX(Date_hour)),
TRIM(MIN(Date_hour))
)
) / 60 AS selected_value
FROM
tbl_2
) AS t2
JOIN tbl_1 ON tbl_1.idticket = t2.idticket
SET t1.DAZ = t2.selected_value;
SELECT
*
FROM
tbl_1;
Query OK, 0 rows affected
Rows matched: 10 Changed: 0 Warnings: 0
+-----+----------+----+
| DAZ | idticket | ID |
+-----+----------+----+
| 4 | 36237886 | 1 |
| 4 | 36237887 | 2 |
| 4 | 36237888 | 3 |
| 4 | 36237889 | 4 |
| 4 | 36237890 | 5 |
| 4 | 36237891 | 6 |
| 4 | 36237892 | 7 |
| 4 | 36237893 | 8 |
| 4 | 36237894 | 9 |
| 4 | 36237895 | 10 |
+-----+----------+----+
10 rows in set
I need this output:
+-----+----------+----+
| DAZ | idticket | ID |
+-----+----------+----+
| 4 | 36237886 | 1 |
| | 36237887 | 2 |
| | 36237888 | 3 |
| | 36237889 | 4 |
| | 36237890 | 5 |
| | 36237891 | 6 |
| | 36237892 | 7 |
| | 36237893 | 8 |
| | 36237894 | 9 |
| | 36237895 | 10 |
+-----+----------+----+
the solution. 
mysql> UPDATE tbl_1
SET DAZ = NULL;
UPDATE tbl_1 t1
JOIN (
SELECT
idticket,
TIME_TO_SEC(
TIMEDIFF(
TRIM(MAX(Date_hour)),
TRIM(MIN(Date_hour))
)
) / 60 AS event_time
FROM
tbl_2
GROUP BY
idticket
) AS t2 ON t1.idticket = t2.idticket
SET t1.DAZ = t2.event_time;
SELECT
*
FROM
tbl_1;
Query OK, 1 row affected
Rows matched: 10 Changed: 1 Warnings: 0
Query OK, 1 row affected
Rows matched: 1 Changed: 1 Warnings: 0
+------+----------+----+
| DAZ | idticket | ID |
+------+----------+----+
| 4 | 36237886 | 1 |
| NULL | 36237887 | 2 |
| NULL | 36237888 | 3 |
| NULL | 36237889 | 4 |
| NULL | 36237890 | 5 |
| NULL | 36237891 | 6 |
| NULL | 36237892 | 7 |
| NULL | 36237893 | 8 |
| NULL | 36237894 | 9 |
| NULL | 36237895 | 10 |
+------+----------+----+
10 rows in set
there is no need to TRIM a datetime value – that doesn’t even make sense
ok, thank you!
mysql> UPDATE tbl_1
SET DAZ = NULL;
UPDATE tbl_1 t1
JOIN (
SELECT
idticket,
TIME_TO_SEC(
TIMEDIFF(
MAX(Date_hour),
MIN(Date_hour)
)
) / 60 AS event_time
FROM
tbl_2
GROUP BY
idticket
) AS t2 ON t1.idticket = t2.idticket
SET t1.DAZ = t2.event_time;
SELECT
*
FROM
tbl_1;
Query OK, 1 row affected
Rows matched: 10 Changed: 1 Warnings: 0
Query OK, 1 row affected
Rows matched: 1 Changed: 1 Warnings: 0
+------+----------+----+
| DAZ | idticket | ID |
+------+----------+----+
| 4 | 36237886 | 1 |
| NULL | 36237887 | 2 |
| NULL | 36237888 | 3 |
| NULL | 36237889 | 4 |
| NULL | 36237890 | 5 |
| NULL | 36237891 | 6 |
| NULL | 36237892 | 7 |
| NULL | 36237893 | 8 |
| NULL | 36237894 | 9 |
| NULL | 36237895 | 10 |
+------+----------+----+
10 rows in set