SQL Count to include zero values

Question

I have created the following stored procedure that is used to count the number of records per day between a specific range for a selected location:

[dbo].[ge         


        

Answer 1

When there is no data to count, there is no row to return.

If you want to include empty days as a 0, you need to create a table (or temporary table, or subquery) to store the days, and left join to your query from that.

eg: something like

SELECT 
    COUNT(*) AS counted_leads,  
    CONVERT(VARCHAR, DATEADD(dd, 0, DATEDIFF(dd, 0, Time_Stamp)), 3) as TIME_STAMP  
    FROM 
        TableOfDays
           left join
        HL_Logs 
           on TableOfDays.Date = convert(date,HL_Logs.Time_Stamp)
           and ID_Location = @LOCATION 
    WHERE TableOfDays.Date between @BEGIN and @END 
    GROUP BY DATEADD(dd, 0, DATEDIFF(dd, 0, Time_Stamp))