install_blog fails when there are more than 8k of blogs in the database

[Kyrylo]

WP stated to fail on install_blog call once we reached 8k of blogs. Users are not able to create blogs via /wp-signup.php. Neither are superadmins able to create blogs via the wp-admin network interface.

The call stack is as follows:

> install_blog ( $blog_id, $blog_title )   // /wp-includes/ms-functions.php
>> make_db_current_silent();               // /wp-includes/ms-functions.php
>>> dbDelta($wp_queries);                  // /wp-admin/includes/upgrade.php
>>>> $wpdb->get_col('SHOW TABLES;')        // /wp-admin/includes/upgrade.php

The last one: $wpdb->get_col('SHOW TABLES;') - is a heave MySQL query and if your database is set to check the integrity of tables - PHP fails via time out.

It is desirable to have a simple and more quicker blog set up.

Currently we had to patch with the code that simply generates 9 blog tables and is not querying about 70,000 tables in the database.

[nacin]

#17998