How do I set SITE_URL to override the database url info? WordPress

Albert Shala answers:

Have you tried updating it via your functions.php ?
update_option('siteurl','http://example.com/blog');
update_option('home','http://example.com/blog');

Lawrence Krubner comments:

No, I have not tried that yet, but is that not the same as:


define('WP_HOME', $server_base_uri . '/blog/');
define('WP_SITEURL', $server_base_uri . '/blog/');

What is the difference?

Francisco Javier Carazo Gil answers:

Hi Lawrence,

The difference between this:
define('WP_HOME', $server_base_uri . '/blog/');
define('WP_SITEURL', $server_base_uri . '/blog/');

And this:
update_option('siteurl','http://example.com/blog');
update_option('home','http://example.com/blog');

Is the next. The first one defines a preprocessor directive that will override value in database but the second one change this value (the value is placed in wp_options).

Francisco Javier Carazo Gil comments:

What would I do to solve your problem?

0) Do define and update_options
1) Find the bad URL in all your files of your theme and if you find it replace it
2) Update the bad value in your database. Some values are serialized, you won't be able to execute a standard SQL query, you will have to use this one: http://interconnectit.com/124/search-and-replace-for-wordpress-databases/ (the perfect tool :))
3) Switch off any cache system

Lawrence Krubner comments:

So if I do this then I automate the updating of the values in the database? That would be fantastic. So why does anyone ever do:

define('WP_HOME', 'http://www.mysite.com/';
define('WP_SITEURL', 'http://www.mysite.com');

Why not always use update_option ?

Francisco Javier Carazo Gil comments:

Well, use define is faster than update_option.

If you use define, WordPress won't make any SELECT query against database, so it is faster, but at the same time, the best option is make the two actions: update in DB and define.

Spencer Tomosvary answers:

This sounds like it is clearly an issue with your database and serialized data that can be resolved a few different ways...

With some clever mysql commands..
this probably won't work and you've probably tried it already but very carefully and painstakingly replacing urls on your .sql file (from the phpmyadmin export) in a text editor...

and now I'm getting closer to an answer for you...

I don't know how many database backups you have, but hopefully you have a backup of it from when everything was last working correctly, before migrating to a new domain.

Each time you've changed the domain, updated the urls from the wp-admin dashboard or functions.php or phpmyadmin or text editor, your're adding complications to it.. you want to back track as far as possible so you have as few as possible variations in the urls you need to modify..

here is another possibility worth mentioning...

Load the site and DB back up on the last url it was where it worked.. do an export of the contents, theme options and widgets (there is a nice plugin out there to download widget data in a json file - also some other plugins I've seen to download all your plugin settings and serialized data in a json file)

Then install a new instance of wordpress and import all the data..

Okay finally here the possible best solution for you... Using the oldest .sql backup you have (to avoid all the URL changes and modifications you made in trying to solve the problem which are just making it worse) go to this url:
[[LINK href="http://interconnectit.com/124/search-and-replace-for-wordpress-databases/"]][[/LINK]]

http://interconnectit.com/124/search-and-replace-for-wordpress-databases/

Download and install the tool on your server (very easy) and run it.. This can swap out/replace your urls properly unlike a text editor and should hopefully fix the problem for you. If for some reason this doesn't work, I'd go back and try the second to last option I mentioned.

:)

Lawrence Krubner comments:

This looks like a very good tool:

[[LINK href="http://interconnectit.com/124/search-and-replace-for-wordpress-databases/"]]http://interconnectit.com/124/search-and-replace-for-wordpress-databases/[[/LINK]]

Thanks for the tip.