The last step in writing queries is to filter the data that is returned to present appropriate information to the user. Some common examples include showing a specific node, getting a list of nodes that a specific user created, getting a list of nodes that were created by a user after a specific date, and so on.
Conditions correlate to the WHERE clause of an SQL statement or a HAVING clause in a query with a GROUP BY clause. Conditions can be added to a query using either the condition method or the where method. The signatures of each method are as follows:
condition($field, $value = NULL, $operator = NULL) where($snippet, $args = array())
The main difference between these two methods is that the condition method allows standard operations to be easily encoded. The where clause allows you to enter an arbitrary SQL snippet for the condition. The SQL snippet is not validated for consistency across databases so you should ensure that it is well supported if you...