Question

I having this problem with query these two table do not have any link between and I am trying to combine. Table 1 have effective and expiration date in which have to be tied to table 2 of PollDate. PollDate must not lies in between the effective and expiration date.

Table 1
ClientID    EffectiveDate       ExpirationDate
1       2009-04-01 00:00:00.000 2009-12-18 00:00:00.000
1       2010-02-12 00:00:00.000 2010-03-05 00:00:00.000
1       2010-05-18 00:00:00.000 NULL
1       2009-12-21 00:00:00.000 2010-02-08 00:00:00.000
1       2010-12-19 00:00:00.000 2009-12-20 00:00:00.000

Table 2
ClientID    PollDate
1       2009-12-20 00:00:00.000
1       2009-12-19 00:00:00.000
1       2010-02-12 00:00:00.000
1       2010-02-27 00:00:00.000
1       2010-05-19 00:00:00.000
1       2010-05-29 00:00:00.000
1       2010-05-30 00:00:00.000
1       2010-05-31 00:00:00.000
1       2010-06-05 00:00:00.000
1       2010-06-25 00:00:00.000
1       2010-06-27 00:00:00.000
1       2010-07-02 00:00:00.000
1       2010-08-04 00:00:00.000
1       2010-08-20 00:00:00.000

Result
ClientID    inValidDate
1       2009-12-20 00:00:00.000
1       2009-12-19 00:00:00.000    

Answer 1

The following is a slight variation of @AJP’s result – just accounting for NULL values in ExpirationDate:

CREATE TABLE #Table1
(
    [ClientID] INT,
    [EffectiveDate] DATETIME,
    [ExpirationDate] DATETIME
)

INSERT INTO #Table1
(
    [ClientID],
    [EffectiveDate],
    [ExpirationDate]
)
SELECT 1, '2009-04-01', '2009-12-18' UNION
SELECT 1, '2010-02-12', '2010-03-05' UNION
SELECT 1, '2010-05-18', NULL UNION
SELECT 1, '2009-12-21', '2010-02-08' UNION
SELECT 1, '2010-12-19', '2009-12-20'

CREATE TABLE #Table2
(
    [ClientID] INT,
    [PollDate] DATETIME
)

INSERT INTO #Table2
(
    [ClientID],
    [PollDate]
)
SELECT 1, '2009-12-20' UNION
SELECT 1, '2009-12-19' UNION
SELECT 1, '2010-02-12' UNION
SELECT 1, '2010-02-27' UNION
SELECT 1, '2010-05-19' UNION
SELECT 1, '2010-05-29' UNION
SELECT 1, '2010-05-30' UNION
SELECT 1, '2010-05-31' UNION
SELECT 1, '2010-06-05' UNION
SELECT 1, '2010-06-25' UNION
SELECT 1, '2010-06-27' UNION
SELECT 1, '2010-07-02' UNION
SELECT 1, '2010-08-04' UNION
SELECT 1, '2010-08-20'

SELECT
    t2.[ClientID],
    t2.[PollDate] AS 'inValidDate'
FROM
    #Table1 AS t1
JOIN
    #Table2 AS t2
ON
    (t2.[PollDate] < t1.[EffectiveDate]
OR  t2.[PollDate] > ISNULL(t1.[ExpirationDate], '9999-12-31'))
AND t1.ClientID = t2.ClientID -- Not clear from your question if this is necessary