dbKeys()

The function dbKeys() lists all keys stored in the Database for Contents. If a subKey is specified, the functions returns all keys beginning with this subkey.

More details and example can be found in the chapter Data Fragments in PHP code and with dbSet()

array dbKeys([string subKey])

• subKey (optional)
  If a subkey is specified then only keys beginning with this subkey are listed. For example, if the subkey is 'A', you will get “A001”, “A002”, “AA00”, “Alpha”, etc., but not “B001” or “100”.