Repeating rows from right join

Question

My application saves logs that need to be taken at least one time during each of the 3 different time periods during the day. So ideally 3 logs per day, each with a unique time period ID. I need to write an exception report (MSSQL 2008) that will show when a time period is missed for any given day. I have a LogTimePeriods table that contains 3 rows for each of the time periods. The Logs table contains the LogTimePeriodID so I do not need to do any logic to see what Time period the log belongs in (that is done via the application).

I know I need something along the lines of a right/left join to try to match all the LogTimePeriodID for every Log row for a given date. I cant seem to make any progress. Any help is appreciated! Thanks for reading.

SQL Fiddle

EDIT: Desired output below

Date | LogPeriodID
6/3 | 3
6/5 | 2
6/5 | 3

Answer 1

Your SQL Fiddle is set to use MYSQL, not SQL Server 2008, so I can't test my answer against your data: however, based on my understanding of your requirements and assuming you are querying a SQL 2008 database, the following example should work for you (the references to my table variables would obviously be replaced with your actual tables).

DECLARE @StartDate DATE = '06/04/2014'
DECLARE @EndDate DATE = GETDATE();
DECLARE @LogTimePeriod TABLE (LogTimePeriodID INT IDENTITY(1,1), TimePeriod VARCHAR(20))
INSERT INTO @LogTImePeriod (TimePeriod) SELECT '00:00 - 07:59'
INSERT INTO @LogTImePeriod (TimePeriod) SELECT '08:00 - 15:59'
INSERT INTO @LogTImePeriod (TimePeriod) SELECT '16:00 - 23:59'


DECLARE @logs TABLE (LogDataID INT IDENTITY(1,1), LogDate DATE, SomeInformation VARCHAR(10), LogTimePeriodID INT)
INSERT INTO @logs (SomeInformation, LogDate, LogTimePeriodID) SELECT 'abc', '6/4/2014', 1
INSERT INTO @logs (SomeInformation, LogDate, LogTimePeriodID) SELECT 'def', '6/4/2014', 2
INSERT INTO @logs (SomeInformation, LogDate, LogTimePeriodID) SELECT 'ghi', '6/4/2014', 3
INSERT INTO @logs (SomeInformation, LogDate, LogTimePeriodID) SELECT 'abc', '6/5/2014', 1
INSERT INTO @logs (SomeInformation, LogDate, LogTimePeriodID) SELECT 'def', '6/5/2014', 2;


WITH dates AS (
     SELECT CAST(@StartDate AS DATETIME) 'date'
     UNION ALL
     SELECT DATEADD(dd, 1, t.date) 
       FROM dates t
      WHERE DATEADD(dd, 1, t.date) <= @EndDate)

SELECT ltp.LogTimePeriodID, ltp.TimePeriod, dates.date
FROM 
    @LogTimePeriod ltp
     INNER JOIN 
    dates ON 1=1
     LEFT JOIN 
    @logs ld ON 
        ltp.LogTimePeriodID = ld.LogTimePeriodID AND
        dates.date = ld.LogDate
WHERE ld.LogDataID IS NULL
 OPTION (MAXRECURSION 1000) -- 0 is unlimited, 1000 limits to 1000 rows 

Answer 2

SQLServer 2008 has the EXCEPT keyword that subtract the second recordset from the first.
In this case it's possible to generate all the possible logs and remove from those the ones in the logs table, that will left the logs not present in the table.

SELECT DISTINCT StartDateTime, StartTime, EndTime
FROM   Logs
       CROSS JOIN LogTimePeriods
EXCEPT
SELECT StartDateTime, StartTime, EndTime
FROM   LogTimePeriods ltp
       LEFT  JOIN logs l ON l.LogTimePeriodID = ltp.LogTimePeriodID
ORDER BY StartDateTime, StartTime

SQLFiddle demo with you data converted to SQLServer 2008