Firebird - форматирование даты

Громоздко, но работает (формат: YYYYMMDD HHMMSS)

SELECT
    LPAD( EXTRACT( YEAR FROM CURRENT_TIMESTAMP ), 4, '0' ) ||
    LPAD( EXTRACT( MONTH FROM CURRENT_TIMESTAMP ), 2, '0' ) ||
    LPAD( EXTRACT( DAY FROM CURRENT_TIMESTAMP ), 2, '0' ) || ' ' ||
    LPAD( EXTRACT( HOUR FROM CURRENT_TIMESTAMP ), 2, '0' ) ||
    LPAD( EXTRACT( MINUTE FROM CURRENT_TIMESTAMP ), 2, '0' ) || 
    LPAD( TRUNC( EXTRACT( SECOND FROM CURRENT_TIMESTAMP ) ), 2, '0' )
FROM
    RDB$DATABASE


Получить номер квартала (1,2,3,4) можно так:

SELECT  (EXTRACT(MONTH FROM CURRENT_TIMESTAMP)-1)/3+1 as Q  FROM RDB$DATABASE

А полугодие (1,2) - так:

SELECT  (EXTRACT(MONTH FROM CURRENT_TIMESTAMP)-1)/6+1 as H  FROM RDB$DATABASE