project is written on php.
There is timestamp field in mysql it updates automatically. In one case I don`t need update this field. Can I gibe instruction not to update this field in this queries without getting timestamp value.
You should change it to DEFAULT CURRENT_TIMESTAMP otherwise it will auto-update. From the manual:
In a CREATE TABLE statement, the first TIMESTAMP column can be declared in any of the following ways:
With both DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses, the column has the current timestamp for its default value, and is automatically updated.
With neither DEFAULT nor ON UPDATE clauses, it is the same as DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP.
With a DEFAULT CURRENT_TIMESTAMP clause and no ON UPDATE clause, the column has the current timestamp for its default value but is not automatically updated.
Edit the column in phpMyAdmin and unselect the option for "on update current timestamp."
Related
I am trying to update date whenever any updates occur on the record, the field type is datetime and I set the default value to CURRENT_TIMESTAMP. when update sql is excuted the result is all zeros!
0000-00-00 00:00:00
$sql = 'INSERT INTO product_shop_offers (id,product_id,shop_id,price,currency_id,added_by,last_update)'
. ' VALUES (?,?,?,?,?,?,?) ON DUPLICATE KEY UPDATE id=?,shop_id=?,price=?,currency_id=?,added_by=?,last_update=?';
$this->db->query($sql, array(
$storeInfoArray['recordId'],
$productId,
$storeInfoArray['storeNameNo'],
$storeInfoArray['price'],
$storeInfoArray['currency'],
$addedBy,
'CURRENT_TIMESTAMP()',
$storeInfoArray['recordId'],
$storeInfoArray['storeNameNo'],
$storeInfoArray['price'],
$storeInfoArray['currency'],
$addedBy,
'CURRENT_TIMESTAMP()'
))
Note: I checked Similar problem question but I didn't understand the problem!!can somebody help please.
Is it because you are binding in the string 'CURRENT_TIMESTAMP()'.. I'm not sure you can do that and it is being converted to zeros.
If you have the default set in the database, why bother binding it in at all? Just remove the field from the statement.. oh and you'll need to add the attribute ON UPDATE CURRENT_TIMESTAMP to the column:
ALTER TABLE product_shop_offers
MODIFY COLUMN last_update DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP;
If you need it otherwise, you may have to write it into the query directly.
I think it should be helpful for you
MySQL CURRENT_TIMESTAMP field updates on every update
Change CURRENT_TIMESTAMP() to NOW()
Another possible way is to set the field type from datetime to timestamp
I have been making tables with a modified row which is time stamped.
`modified` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
I am seeking to rename this as bookedinand timestamp the day of entry into the database.
i have looked on the net for a solution at sites like http://www.w3schools.com/sql/func_curdate.asp
And cant seem to find a solution that works or is what i need.
I tried to edit it in the databse myself but with no luck. as you can tell im a extremity novice
Instead of w3schools you really should use the actual MySQL documentations. http://dev.mysql.com/doc/refman/5.1/en/alter-table.html
alter table tablename change `modified` `bookedin` timestamp NOT NULL DEFAULT
CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP;
Or maybe just
alter table tablename change `modified` `bookedin` timestamp NOT NULL DEFAULT
CURRENT_TIMESTAMP;
I think the on update may just be part of the timestamp datatype. And, I think that altering the name of the table might cause all the rows to update their timestamp to the date you did it. So you might want to make a copy of the table and try it out first. I remember running into a problem like that once that made me switch from using TIMESTAMP to DATETIME.
I want to store the time at which the table was accessed/modified. I know how to put current timestamp.
But what we must do to store the updated timestamp ?
I am not sure what exactly you are looking for but below query might be helpful.
you can create/upate your table to have "On Update Current_timestamp"
CREATE TABLE t1 (
ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);
To update a timestamp when accessing a record you could use a stored procedure to select the records and then update the timestamp fields.
#Suresh Kamrushi has suggested a solution for updating the timestamp when the record is modified.
This seems like a really simple one but I'm struggling to figure it out. I want a column in my database that lists when a record was first created and another column that says when it was updated. It's my understanding I should be able to do all this just using MySQL. All help is appreciated :)
This stinks still no answer, reasons I'm already starting to miss Ruby on Rails...
You will probably need to use a combination of the Datetime datatype and the Timestamp data type. I would set my created column as a DateTime with a DEFAULT NOW(), and my updated column as a Timestamp with DEFAULT CURRENT_TIMESTAMP and an ON UPDATE CURRENT_TIMESTAMP attribute.
Here are the docs for the Timestamp dt:
http://dev.mysql.com/doc/refman/5.0/en/timestamp.html
In a CREATE TABLE statement, the first TIMESTAMP column can be declared in any of the following ways:
With both DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses, the column has the current timestamp for its default value, and is automatically updated.
With neither DEFAULT nor ON UPDATE clauses, it is the same as DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP.
With a DEFAULT CURRENT_TIMESTAMP clause and no ON UPDATE clause, the column has the current timestamp for its default value but is not automatically updated.
With no DEFAULT clause and with an ON UPDATE CURRENT_TIMESTAMP clause, the column has a default of 0 and is automatically updated.
With a constant DEFAULT value, the column has the given default and is not automatically initialized to the current timestamp. If the column also has an ON UPDATE CURRENT_TIMESTAMP clause, it is automatically updated; otherwise, it has a constant default and is not automatically updated.
To fulfill your question and for others viewing this question, here is the answer. Note this was written for MySQL 5.x.
DROP TABLE IF EXISTS `test1`;
CREATE TABLE `test1` (
`id` INT NULL AUTO_INCREMENT ,
`name` varchar(50) NOT NULL ,
`created` DATETIME ,
`updated` DATETIME ,
PRIMARY KEY (`id`),
INDEX (`name`)
);
DELIMITER $$
DROP TRIGGER IF EXISTS `test1_created`$$
CREATE TRIGGER `test1_created` BEFORE INSERT ON `test1`
FOR EACH ROW BEGIN
SET NEW.`created` = UTC_TIMESTAMP();
SET NEW.`updated` = UTC_TIMESTAMP();
END;
$$
DROP TRIGGER IF EXISTS `test1_updated`$$
CREATE TRIGGER `test1_updated` BEFORE UPDATE ON `test1`
FOR EACH ROW BEGIN
SET NEW.`updated` = UTC_TIMESTAMP();
END;
$$
DELIMITER ;
Note
You could use TIMESTAMP for the updated column which would have automatically updated the value thus not requiring the BEFORE UPDATE trigger, however TIMESTAMP has a range from 1970 to 2038 which is fast approaching and I like to think my applications will live forever :). Although TIMESTAMP is only 4bytes while DATETIME is 8bytes.
TIMESTAMP range '1970-01-01 00:00:01' UTC to '2038-01-19 03:14:07' UTC
DATETIME range '1000-01-01 00:00:00' to '9999-12-31 23:59:59'
From the MySQL 5.0 Certification Guide:
CREATE TABLE ts_test5 (
created TIMESTAMP DEFAULT 0,
updated TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
data CHAR(30)
);
To control the initialization and update behaviour of a TIMESTAMP column, you add either or both of the DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP attributes to the column defintion when creating the table with CREATE TABLE...
and
...if you do not specify either of the DEFAULT CURRENT_TIMESTAMP or ON UPDATE CURRENT_TIMESTAMP attributes when creating a table, MySQL automatically assigns BOTH to the first TIMESTAMP column
Also
you cannot use DEFAULT CURRENT_TIMESTAMP with one column and ON UPDATE CURRENT_TIMESTAMP with another
If you can't use the timestamp fields with default attributes that Paul W has suggested, you can use AFTER INSERT and AFTER UPDATE triggers to populate the fields.
You will need two fields "Created" and
"Updated" with type datetime. When a
new entry is inserted then insert
"Created" with current time stamp.
When a update is happening insert
"Updated" with the current time stamp,
and let the "Created" field remain as
it is.
For current time stamp you can use
NOW() in your mysql query.
I have a database table in mysql with a field that is of "TIMESTAMP" type. I need help writing the SQL query to update the field with the current timestamp.
UPDATE tb_Test set dt_modified = ?????
Use:
UPDATE tb_Test
SET dt_modified = CURRENT_TIMESTAMP
WHERE ? -- if you don't specify, ALL dt_modified values will be updated
You can use NOW() instead of CURRENT_TIMESTAMP, but CURRENT_TIMESTAMP is ANSI standard so the query can be ported to other databases.
ALTER TABLE tb_Test MODIFY COLUMN dt_modified TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP
Now whenever any field is changed the dt_modified will be updated by the special trigger.