Porting Considerations for SQL
From InterBase
Go Up to Requirements for All Applications (Embedded SQL Guide)
When porting existing SQL applications to InterBase, other considerations may be necessary. For example, many SQL variants require that host variables be declared between BEGIN DECLARE SECTION and END DECLARE SECTION statements; InterBase has no such requirements, but gpre can correctly handle section declarations from ported applications. For additional portability, declare all host-language variables within sections.