WP Custom plugin: Create table and insert data once. - php

Question

This is my complete Wordpress plugin file:
<?php
function wp_create_table_install()
{
global $wpdb;
$table_name = $wpdb->prefix.'createtable';
$sql = 'CREATE TABLE '.$table_name.'(
id INT(11) NOT NULL PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(75)
);';
require_once(ABSPATH.'wp-admin/includes/upgrade.php');
dbDelta($sql);
}
function wp_create_table_insert_data()
{
global $wpdb;
$table_name = $wpdb->prefix.'createtable';
$id = 1;
$name = 'WP Create Table!';
$wpdb->insert($table_name, array('id' => $id, 'name' => $name));
}
register_activation_hook(__FILE__, 'wp_create_table_install');
register_activation_hook(__FILE__, 'wp_create_table_insert_data');
?>
When I activate the plugin, it always tries to create a table and insert data. How could I do it once, just in the first plugin activation?
Thank you.

Answer 1

A quicker way would be to add [IF NOT EXISTS] in your CREATE statement so that you don't get an error if your table already exists.

Answer 2

Before running CREATE TABLE, you could query information_schema.tables to check to see whether or not the table already exists.

Answer 3

Unfortunately, there's no way to run something on "install" - surprisingly, WordPress doesn't provide any hooks for install as opposed to activation!
The way people cope with this is to set and test an option - if the option is not set, then create the tables, and if it is set do nothing or do a DB upgrade. Options are read in and cached so there is no performance penalty to doing this.
$opt = get_option(MYPLUGIN_OPTIONS);
$opt['dbversion'] = 100;
...
update_option(MYPLUGIN_OPTIONS, $opt);