SQLite Forum

When is SELECT ... FROM with no table-or-subquery valid.
The syntax diagram for SELECT allows a FROM not followed by any table-or-subquery. The <b>Determination of input data (FROM clause processing)</b> section of the description says "If a FROM clause is specified, the data on which a simple SELECT query operates comes from the one or more tables or subqueries". What happens if there are zero tables or subqueries as apparently permitted by the syntax diagram?