SQL has a few wildcard characters. They are mostly used within the LIKE syntax however they can also be used in other conditional statements. There are several different ways to use wildcards but the result is that the DBA can use a partial text string to find a specific entry within the database. The following are the examples of the different wildcards and how they are used.
|%||Returns all values that could be held by this place holder|
|_||Allows exactly one character to be wild|
|[charlist]||Any character in the provided list|
|[^charlist] or [!charlist]||Any character not in the list|