select '' || cast( 1 as SMALLINT ) from rdb$database;
select '' || cast( 1 as INTEGER ) from rdb$database;
select '' || cast( 1 as BIGINT ) from rdb$database;
select '' || cast( TRUE as BOOLEAN ) from rdb$database; -- Overflow occurred during data type conversion.
                                                        -- conversion error from string "BOOLEAN".
select '' || cast( 1.1 as FLOAT ) from rdb$database;
select '' || cast( 1.1 as DOUBLE PRECISION ) from rdb$database;
select '' || cast( 1.1 as NUMERIC(3,3) ) from rdb$database;
select '' || cast( 1.1 as DECIMAL(3,3) ) from rdb$database;
select '' || cast( '2015-01-01' as DATE ) from rdb$database;
select '' || cast( '10:51:59' as TIME ) from rdb$database;
select '' || cast( '2015-01-01 10:51:59' as TIMESTAMP ) from rdb$database;
select '' || cast( 'char text' as CHAR(20) ) from rdb$database;
select '' || cast( 'varchar text' as VARCHAR(20) ) from rdb$database;
select '' || cast( 'blob text' as BLOB ) from rdb$database;

select cast( TRUE as varchar(20) ) from rdb$database;