How to split the date into monthwise

Question

Using SQL Server 2000

I want to save the details in month wise

User Entry

ID = 001
Fromdate = 01/01/2012
Todate = 29/03/2012

ID = 002
Fromdate =         


        

Answer 1

First, create and populate a calendar table that has the following columns (at least):

CREATE TABLE dbo.Calendar (
    BaseDate datetime NOT NULL PRIMARY KEY,
    Period char(7) NOT NULL,
    YearNumber int NOT NULL,
    MonthNumber int NOT NULL,
    IsFirstDayOfMonth bit NOT NULL,
    IsLastDayOfMonth bit NOT NULL
)

Then this query will return the data you need, for one pair of fromdate and todate but you can of course put it into a stored procedure and call it once per user input or whatever way you execute SQL from your application:

declare @ID char(3), @FromDate datetime, @ToDate datetime

select @ID ='001', @FromDate = '20120107', @ToDate = '20120917'

select
    @ID as 'ID',
    c.Period,
    case when c.IsFirstDayOfMonth = 0x0 then @FromDate else c.BaseDate end as 'FromDate',
    case when @ToDate < c1.BaseDate then @ToDate else c1.BaseDate end as 'ToDate'
from
    dbo.Calendar c
    join dbo.Calendar c1
    on c.YearNumber = c1.YearNumber and c.MonthNumber = c1.MonthNumber
where
    c.BaseDate between @FromDate and @ToDate and
    (c.IsFirstDayOfMonth = 0x1 or c.BaseDate = @FromDate) and
    c1.IsLastDayOfMonth = 0x1

Answer 2

You could use a numbers table (have you got one yet?) to generate the months:

SELECT
  ID,
  Period   = RIGHT(CONVERT(varchar(10), MonthStart, 103), 7),
  /*
  alternatively:
  Period = RIGHT('0' + RTRIM(MONTH(MonthStart), 2) + '/' + RTRIM(YEAR(MonthStart)),
  */
  FromDate = CASE WHEN RangeStart > MonthStart THEN RangeStart ELSE MonthStart END,
  ToDate   = CASE WHEN RangeEnd   < MonthEnd   THEN RangeEnd   ELSE MonthEnd   END
FROM (
  SELECT
    ID,
    RangeStart,
    RangeEnd,
    Monthstart,
    MonthEnd = DATEADD(DAY, -1, DATEADD(MONTH, 1, Monthstart))
  FROM (
    SELECT
      ID         = @ID,
      RangeStart = @RangeStart,
      RangeEnd   = @RangeEnd,
      MonthStart = DATEADD(MONTH, DATEDIFF(MONTH, 0, @RangeStart), 0)
    FROM numbers
    WHERE Number BETWEEN 0 AND DATEDIFF(MONTH, @RnageStart, @RangeEnd)
  ) m
) m

As a temporary substitute for the numbers table, you could use the master..spt_values system table, or, more exactly, its particular subset where type = 'P'. So, you can just replace the FROM numbers above with this subselect:

FROM (
  SELECT Number
  FROM master..spt_values
  WHERE type = 'P'
) numbers