[PHP-DB] MySQL version issue
As some of you will recall, I enquired on this list about versions of MySQL and PHP a while back regarding and issue wit using the 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries. Having upgraded our in-house system to PHP5 and MySQL 4 the issue was no longer a problem. However I have subsequently enquired with our out-of-house web host and they are still using PHP 4.1.2 and MySQL 3.25.58. As one of the purposes of asking them was to establish if I could easily upload from my database to the remote database, I now have a problem. I was planning to use a compare and update script that used 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries to add or change items on the remote server. However I can't, as it's a MySQL4 feature and the database to which I am writing ain't using MySQL4! Any ideas about how I can create a MySQL3 compliant substitute for the 'ON DUPLICATE KEY UPDATE' Query action? -- Mark Benson http://homepage.mac.com/markbenson -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP-DB] MySQL version issue
Hi Mark, I guess the best way would be to use some php and sql and let the application do the checking. First run a query to acertain if the key is present, if yes then update the main record else insert a new record. bascially you just need to bring the SQL logic into the app logic. Bastien From: Mark Benson [EMAIL PROTECTED] To: php-db@lists.php.net Subject: [PHP-DB] MySQL version issue Date: Tue, 04 Jan 2005 14:43:48 + As some of you will recall, I enquired on this list about versions of MySQL and PHP a while back regarding and issue wit using the 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries. Having upgraded our in-house system to PHP5 and MySQL 4 the issue was no longer a problem. However I have subsequently enquired with our out-of-house web host and they are still using PHP 4.1.2 and MySQL 3.25.58. As one of the purposes of asking them was to establish if I could easily upload from my database to the remote database, I now have a problem. I was planning to use a compare and update script that used 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries to add or change items on the remote server. However I can't, as it's a MySQL4 feature and the database to which I am writing ain't using MySQL4! Any ideas about how I can create a MySQL3 compliant substitute for the 'ON DUPLICATE KEY UPDATE' Query action? -- Mark Benson http://homepage.mac.com/markbenson -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DB] MySQL version issue
It seems to me that the _mysql manual_ gives a most straightforward and useful explanation: If you specify the ON DUPLICATE KEY UPDATE clause (new in MySQL 4.1.0), and a row is inserted that would cause a duplicate value in a UNIQUE index or PRIMARY KEY, an UPDATE of the old row is performed. For example, if column a is declared as UNIQUE and already contains the value 1, the following two statements have identical effect: mysql INSERT INTO table (a,b,c) VALUES (1,2,3) ON DUPLICATE KEY UPDATE c=c+1; mysql UPDATE table SET c=c+1 WHERE a=1; The rows-affected value is 1 if the row is inserted as a new record and 2 if an existing record is updated. Note: If column b is unique too, the INSERT would be equivalent to this UPDATE statement instead: mysql UPDATE table SET c=c+1 WHERE a=1 OR b=2 LIMIT 1; If a=1 OR b=2 matches several rows, only one row is updated! In general, you should try to avoid using the ON DUPLICATE KEY clause on tables with multiple UNIQUE keys. Or, you might find a more interesting answer on a MySQL list. Doug Mark Benson wrote: As some of you will recall, I enquired on this list about versions of MySQL and PHP a while back regarding and issue wit using the 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries. Having upgraded our in-house system to PHP5 and MySQL 4 the issue was no longer a problem. However I have subsequently enquired with our out-of-house web host and they are still using PHP 4.1.2 and MySQL 3.25.58. As one of the purposes of asking them was to establish if I could easily upload from my database to the remote database, I now have a problem. I was planning to use a compare and update script that used 'ON DUPLICATE KEY UPDATE' command in MySQL INSERT queries to add or change items on the remote server. However I can't, as it's a MySQL4 feature and the database to which I am writing ain't using MySQL4! Any ideas about how I can create a MySQL3 compliant substitute for the 'ON DUPLICATE KEY UPDATE' Query action? -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
