• StringClass
• DbListClass
• StaticListClass
  Also works for tags (which are of type StaticListClass with Multiple Select and Relational Storage activated).

For DbListClass, the suggest can be used with the user's query (in the field "Hibernate Query", from the class). If the query retrieves two columns from the database (i.e "select distinct obj.name, prop.value from..."), then the first column is used as a "key" and placed in a hidden input, and the value is retrieved using obj.name. If the object does not exist yet, the user must create an object first and then use the suggest feature. If the query retrieves only one column (i.e "select prop.value from...") then the suggest feature does not need a hidden input to retrieve the key. If the user's query retrieves more than 2 columns, the suggest feature ignores the third, fourth...columns.