Performs a database query, using current database connection.

Selects a database using the current or provided database connection.

Enables showing of database errors.

Adds a callback function to a filter hook.

Walks the array while sanitizing the contents.

Adds slashes to a string or recursively adds slashes to strings within an array.

Converts email addresses characters to HTML entities to block spam bots.

Calls the callback functions that have been added to a filter hook.

Adds backslashes before letters and before a number at the start of a string.

Balances tags if forced to, or if the ‘use_balanceTags’ option is set to true.