Listing 4: Code That Creates and Populates the RatesExpand Auxiliary Table
CREATE TABLE RatesExpand
( fromdatetime smalldatetime NOT NULL,
  todatetime   smalldatetime NOT NULL,
  rate         money         NOT NULL,
  PRIMARY KEY(fromdatetime),
  UNIQUE(todatetime),
  CHECK(todatetime > fromdatetime))
INSERT INTO RatesExpand(fromdatetime, todatetime, rate)
  SELECT
    DATEADD(minute,
      DATEDIFF(minute, '19000101', fromtime),
      DATEADD(day, n-1, '20030201')) AS fromdatetime,
    DATEADD(minute,
      DATEDIFF(minute, '19000101', totime),
      DATEADD(day, n-1, '20030201')) AS todatetime,
    rate
  FROM Rates, Nums
  WHERE n <= DATEDIFF(day, '20030201', '20030228') + 1