Question

My DateCompleted return the date and the time. If I would like to group just by the date and ignore the time. How would I go about this?

SELECT  
  Cast(Jobs.DateCompleted AS VarChar) AS 'DateCompleted',
  SUM(Metrics.GB) AS GB, 
  SUM(Metrics.KB) AS KB
FROM Metrics 
INNER JOIN Jobs ON Jobs.JobId = Metrics.JobId 
INNER JOIN Projects ON Projects.ProjectId = Jobs.ProjectId 
INNER JOIN JobTypes ON JobTypes.JobTypeId = Jobs.JobTypeId
WHERE Jobs.DateCompleted BETWEEN '12/01/2012' AND '12/03/2012' 
GROUP BY Jobs.DateCompleted

Answer 1

If you are using SQL Server, then you can convert the value as a varchar with a format that strips the time:

SELECT convert(char(10), Jobs.DateCompleted, 120) AS DateCompleted,
  SUM(Metrics.GB) AS GB, 
  SUM(Metrics.KB) AS KB
FROM Metrics 
INNER JOIN Jobs 
  ON Jobs.JobId = Metrics.JobId 
INNER JOIN Projects 
  ON Projects.ProjectId = Jobs.ProjectId 
INNER JOIN JobTypes 
  ON JobTypes.JobTypeId = Jobs.JobTypeId
WHERE Jobs.DateCompleted Between '12/01/2012' AND '12/03/2012' 
GROUP BY convert(char(10), Jobs.DateCompleted, 120)

If you are using SQL Server 2008+, then you can cast the value as a date:

SELECT cast(Jobs.DateCompleted as date) AS DateCompleted,
  SUM(Metrics.GB) AS GB, 
  SUM(Metrics.KB) AS KB
FROM Metrics 
INNER JOIN Jobs 
  ON Jobs.JobId = Metrics.JobId 
INNER JOIN Projects 
  ON Projects.ProjectId = Jobs.ProjectId 
INNER JOIN JobTypes 
  ON JobTypes.JobTypeId = Jobs.JobTypeId
WHERE Jobs.DateCompleted Between '12/01/2012' AND '12/03/2012' 
GROUP BY cast(Jobs.DateCompleted as date)

Note: I am assuming SQL Server based on your previous tags