Joomla! 1.5 Cookbook
上QQ阅读APP看书,第一时间看更新

Removing content from a table

There might be times you wish to remove JUST the data from a table, such as if a spammer inserts names into your mailing database, or you wish to remove all of the data from any table. There are many times this might come in handy.

You will see how to delete a single row of data and delete the entire data set from the table.

In any case, the same warnings apply.

Tip

BACKUP YOUR DATABASE BEFORE YOU START!

Getting ready

You will need your username and password for accessing your database in your cPanel® and your FileZilla client.

Depending on your hosting you may need your username and password for the database.

You will need a copy of your database. You can use the recipe to EXPORT your data for safety and backup.

How to do it...

  1. Navigate to your main database menu. You should be here:
    How to do it...

    Once again we will review the GUI method first, then the command-line method.

  2. Locate your table of choice - we'll once again use jos_Corn_Syrup as our table. In this example, we WANT to wipe out the data, but not actually remove the table from the database.
    How to do it...
  3. Choose your table as above then scroll down to the bottom of the screen till you see this screen (opened for the screenshot):
    How to do it...
  4. Choose Empty from the above list. This will prompt you and ask if you are SURE you wish to. Choose Yes in the lower left-corner of the screen to EMPTY (also known as TRUNCATE) the table.

    Once done you will see:

    How to do it...

    This shows that the table was 'emptied' out.

    Command line version of Empty (known as Truncate)

  5. Go back to the top of your phpMyAdmin screen and select the SQL button and enter this command (with the table you want):
    TRUNCATE `jos_Corn_Syrup`;
    

    This will ask you to verify it, and if it's correct, click YES in the lower right-hand corner.

How it works

This command instructs the database to REMOVE the contents by erasing the data.

In reality the "truncate" command that is called 'drops' the entire table and recreates it but without data.

However, it will maintain the structure of the database. This is useful in situations where you are developing a site and want to remove the content before you turn it over to a client, or in situations where the data is not needed but the table setup by the extension is.

See also

http://www.packtpub.com/ offers a title for a more extensive training on phpMyAdmin - http://www.packtpub.com/phpmyadmin-3rd-edition/book