9.3.9 Updating dataThis is NOT the latest copy of this book; click here for the latest version.
To update data currently in your database, you use the UPDATE command. You specify all the fields you want to change, and the values you want to change them to like this:
UPDATE usertable SET FirstName = 'Joe', Age = 30;
That statement will change all records in usertable so that they have the FirstName "Joe" and Age "30". We can filter the rows to be updated by using a WHERE clause, just like in SELECT. So, to change all people with FirstName "Joe" to FirstName "Peter", we would use this statement:
UPDATE usertable SET FirstName = 'Peter' WHERE FirstName = 'Joe';
It is quite easy, is not it? UPDATE can also use the LIMIT clause, to allow you to only update the first n matching rows, but this is rarely used.
|
Want to see this stuff in print? PHP in a Nutshell takes the core topics covered here, adds in thousands of edits from the editorial team and myself, and combines them to make an unbeatable reference for PHP programmers at all levels.
My latest book has hundreds more tips on how to use PHP, Apache, and MySQL, plus Perl, Python, shell scripts, performance tuning, and more!
|
