Use the results of a SQL expression to generate options for a DropDownList. The selected items value is the string stored.
The SQL Expression must return two columns: a 'Text' field
that's used for the visible text and a 'Value' field that's used to identify an item. The parameter (or token) @currentId can
be used in the SQL, and will be substituted with the id of the Document / Media or Member that the datatype is a property on.
The Connection string is configured via a drop down selection, which defaults to the current Umbraco database. If there are connection strings defined in the web.config, these become selectable options. (The connection string name
is stored, so migration between environments can all be controlled via the web.config).
<add name="" connectionString="server=;database=;user id=;password=" />
Note: Prior to release v5.0.0 the full connection string value was stored rather than the name to a web.config setting.