CREATE FUNCTION "IsCurWeek" (
IN "ADate" DATE)
RETURNS BOOLEAN
BEGIN
 DECLARE Result BOOLEAN DEFAULT False;
 DECLARE EndDate, StartDate, Temp DATE;
 DECLARE iYear, iMonth, iDay, iDOW INTEGER;

 SET EndDate = CURRENT_DATE;
 SET iDOW = EXTRACT(DAYOFWEEK, EndDate);

 SET Temp = EndDate - CAST(iDOW AS INTERVAL DAY);
 SET iYear = EXTRACT(YEAR, Temp);
 SET iMonth = EXTRACT(MONTH, Temp);
 SET iDay = EXTRACT(DAY, Temp);

 SET StartDate = CAST(CAST(iYear AS VARCHAR) + '-' + CAST(iMonth AS VARCHAR) + '-' + CAST(iDay AS VARCHAR) AS DATE);

 IF ADate BETWEEN StartDate AND EndDate THEN
   SET Result = True;
 ELSE
   SET Result = False;
 END IF;

 RETURN Result;
END

DESCRIPTION 'Boolean function to return TRUE if the given date belongs to current week.'