Title: dbdelta creat table inconsistent behavior
Last modified: August 31, 2016

---

# dbdelta creat table inconsistent behavior

 *  Resolved [sk8ermeb](https://wordpress.org/support/users/sk8ermeb/)
 * (@sk8ermeb)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/)
 * I have been getting really inconsistent behavior with the use of dbdelta recently(
   likely since 4.4.2 upgrade). The following (seemingly a bug) has been driving
   me crazy.
 *     ```
       $table_name = $wpdb->prefix . "rbelegvote";
             $sql = "CREATE TABLE " . $table_name . " (
             id mediumint(9) NOT NULL AUTO_INCREMENT,
             email varchar(120) NOT NULL,
             twitid varchar(120) NOT NULL,
             PRIMARY KEY  (id),
             KEY (email)
             );";
             require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
             dbDelta($sql);
       ```
   
 * works, however putting an underscore in the table name so it becomes:
 *     ```
       $table_name = $wpdb->prefix . "rbe_legvote";
             $sql = "CREATE TABLE " . $table_name . " (
             id mediumint(9) NOT NULL AUTO_INCREMENT,
             email varchar(120) NOT NULL,
             twitid varchar(120) NOT NULL,
             PRIMARY KEY  (id),
             KEY (email)
             );";
             require_once(ABSPATH . 'wp-admin/includes/upgrade.php');
             dbDelta($sql);
       ```
   
 * does not work. I have tried this like 10 times to make sure I wasn’t doing something
   stupid. Can anyone out there tell my why the first one would work and the second
   one wouldn’t? The second one used to work and no longer does, and I think I obeyed
   all the strange spacing requirements for db delta. I am suspecting this has to
   do with the wordpress update but not sure. Thank you in advance

Viewing 5 replies - 1 through 5 (of 5 total)

 *  Moderator [bcworkz](https://wordpress.org/support/users/bcworkz/)
 * (@bcworkz)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194325)
 * Why use dbDelta? Why not `$wpdb->query()`? No restrictions at all, any valid 
   mySQL query accepted.
 *  [catacaustic](https://wordpress.org/support/users/catacaustic/)
 * (@catacaustic)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194335)
 * > Why use dbDelta?
 * Because `dbDelta()` is developed to make changes to any existing tables to match
   the given schema that’s passed into it. Tis is mostly important for updates/upgrades.
   Just using `$wpdb->query()` will break if the table already exists. In a lot 
   of cases this won’t be a big deal, but when you’re developing for a plugin or
   theme that has any possibility of a database update at all, then `dbDelta()` 
   is what should be used.
 * [@sk8ermeb](https://wordpress.org/support/users/sk8ermeb/) – There’s no reason
   for a table name with an underscore to fail as it’s a valid table name. The way
   that I’d suggest testing this is to turn on error reporting (set `define('WP_DEBUG',
   true);` in your `wp-config.php` file) and if it was me I’d also echo out the 
   query string so that I can be sure of what it says. That way you should get any
   errors that occur, and if you don’t see any you can test the SQL string directly
   in phpMyAdmin (or whichever database management tool that you use) to see what
   errors that shows.
 *  Thread Starter [sk8ermeb](https://wordpress.org/support/users/sk8ermeb/)
 * (@sk8ermeb)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194337)
 * So this was only giving this strange behavior I have on a live server and the
   error was from their SQL console:
    `#1005 - Can't create table 'wordpress_i4bkahld3f.
   wp_exrz_rbe_legvote' (errno: -1)` I coudln’t find that sql error number so I 
   opened a support ticket and they responded saying that they were able to re-create
   the issue and a few hours later they closed it saying they created the table 
   for me. I asked for an explanation for for learning sake but have not heard anything.
 * If anyone knows what that sql error number refers to that would be helpful. Thank
   you
 *  [catacaustic](https://wordpress.org/support/users/catacaustic/)
 * (@catacaustic)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194338)
 * After a very qucik search I’ve found others that have the same issue:
 * [http://stackoverflow.com/questions/26980657/mysql-cant-create-table-errno-1](http://stackoverflow.com/questions/26980657/mysql-cant-create-table-errno-1)
 * [http://stackoverflow.com/questions/15152857/mysql-error-code-1005-errno-1](http://stackoverflow.com/questions/15152857/mysql-error-code-1005-errno-1)
 * From those, it looks like it’s a problem with the InnoDB table type having an
   issue that’s sort of there, but really not. It’s most likely come about from 
   repeated attempts to create and destroy that table that the InnoDB engine hasn’t
   quite kept up with as well as it should.
 * The “solution” that’s suggested there is to backup the database, dump/delete 
   it, and restore it from the backup. That _should_ get rid of whatever temporary
   stuff is going on.
 *  Thread Starter [sk8ermeb](https://wordpress.org/support/users/sk8ermeb/)
 * (@sk8ermeb)
 * [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194339)
 * [@catacaustic](https://wordpress.org/support/users/catacaustic/) – Thank you 
   very much! I can have at least a little resolution to my confusion! 🙂

Viewing 5 replies - 1 through 5 (of 5 total)

The topic ‘dbdelta creat table inconsistent behavior’ is closed to new replies.

## Tags

 * [dbDelta()](https://wordpress.org/support/topic-tag/dbdelta/)
 * [inconsistent](https://wordpress.org/support/topic-tag/inconsistent/)
 * [not](https://wordpress.org/support/topic-tag/not/)
 * [tables](https://wordpress.org/support/topic-tag/tables/)
 * [working](https://wordpress.org/support/topic-tag/working/)

 * In: [Hacks](https://wordpress.org/support/forum/plugins-and-hacks/hacks/)
 * 5 replies
 * 3 participants
 * Last reply from: [sk8ermeb](https://wordpress.org/support/users/sk8ermeb/)
 * Last activity: [10 years, 2 months ago](https://wordpress.org/support/topic/dbdelta-creat-table-inconsistent-behavior-1/#post-7194339)
 * Status: resolved

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