How do I query a table?

Question

I am using Contact form 7 and the database extension, the db extension creates a table called wp_CF7DBPlugin_SUBMITS. I have 2 forms on my site, I need to know if the user has completed the 2nd form, so when they return they can skip the 1st form.

I don't even know where to start with this, any help will be much appreciated.

Answer 1

Codex has extensive wpdb reference on how to perform different kinds of requests to database. However in most cases it is best to try to access data with available WP or theme/plugin code first.