SQL Server query - Fill Missing Dates In a Date-Sequenced in SQL using Tally Table

Question

I have a table in database with numbers of tenants, each tenant lists a record of their sales per date. There are instance where in a tenant has NO SALES in particular date/s, t

Answer 1

I love wewesthemenace answer! Up-voted and have saved it for future reference. Here is another suggestion. Use this code in SQL command from Crystal. Left outer join to your table sales. Its long. Its tedious. But its easier to understand if you aren't an SQL expert which describes me pretty well :) If you figured out his answer and it works then disregard this solution.

Note: the from clause isn't serving any function except to satisfy the requirement of having a from clause in an SQL statement like this. If tblSales is a large table consider using one from your database which has less data and still left outer join to tblSales.

    select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','01') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','02') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','03') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','04') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','05') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','06') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','07') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','08') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','09') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','10') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','11') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','12') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','13') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','14') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','15') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','16') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','17') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','18') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','19') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','20') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','21') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','22') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','23') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','24') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','25') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','26') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','27') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','28') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','29') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','30') as DATE) as salesdate
from tblSales
UNION
select distinct
cast(concat(DATEPART(YYYY, GETDATE()),'-',DATEPART(MM,GETDATE()),'-','31') as DATE) as salesdate
from tblSales

Answer 2

You could do this using a Tally Table.

Basically, you use the Tally Table to generate sequence of dates from @startDate to @endDate and CROSS JOIN it to DISTINCT Item to generate all Date-Item combination. Then, the result will be LEFT-JOINed to tblSales to achieve the desired output.

SQL Fiddle

DECLARE
    @startDate  DATE = '20140101',
    @endDate    DATE = '20140105';

WITH E1(N) AS(
    SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
    SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
)
,E2(N) AS(SELECT 1 FROM E1 a, E1 b)
,E4(N) AS(SELECT 1 FROM E2 a, E2 b)
,Tally(N) AS(
    SELECT TOP (DATEDIFF(DAY, @startDate, @endDate) + 1) 
        ROW_NUMBER() OVER(ORDER BY(SELECT NULL))
    FROM E4
)
,CteAllDates(Item, dt) AS(
    SELECT x.Item, DATEADD(DAY, N - 1, @startDate)
    FROM Tally
    CROSS JOIN(
        SELECT DISTINCT Item 
        FROM tblSales
        WHERE [Date] BETWEEN @startDate AND @endDate
    ) AS x
)
SELECT d.*, ts.Sales
FROM CteAllDates d
LEFT JOIN tblSales ts
    ON ts.Item = d.Item
    AND ts.Date = d.dt
WHERE
    ts.[Date] BETWEEN @startDate AND @endDate
ORDER BY d.Item, d.dt

---

Here is an alternative. Instead of the cascading CTEs, use sys.columns to generate the Tally Table.:

DECLARE
    @startDate  DATE = '20140101',
    @endDate    DATE = '20140105';

WITH Tally(N) AS(
    SELECT TOP (DATEDIFF(DAY, @startDate, @endDate) + 1) 
        ROW_NUMBER() OVER(ORDER BY(SELECT NULL))
    FROM sys.columns a, sys.columns b
)
,CteAllDates(Item, dt) AS(
    SELECT x.Item, DATEADD(DAY, N - 1, @startDate)
    FROM Tally
    CROSS JOIN(
        SELECT DISTINCT Item 
        FROM tblSales
        WHERE [Date] BETWEEN @startDate AND @endDate
    ) AS x
)
SELECT d.*, ts.Sales
FROM CteAllDates d
LEFT JOIN tblSales ts
    ON ts.Item = d.Item
    AND ts.Date = d.dt
WHERE
    ts.[Date] BETWEEN @startDate AND @endDate
ORDER BY d.Item, d.dt

---

Result

|    Item |         dt |  Sales |
|---------|------------|--------|
| tenant1 | 2014-01-01 |    100 |
| tenant1 | 2014-01-02 |    100 |
| tenant1 | 2014-01-03 |    100 |
| tenant1 | 2014-01-04 |   NULL |
| tenant1 | 2014-01-05 |    100 |
| tenant2 | 2014-01-01 |    100 |
| tenant2 | 2014-01-02 |   NULL |
| tenant2 | 2014-01-03 |   NULL |
| tenant2 | 2014-01-04 |    100 |
| tenant2 | 2014-01-05 |   NULL |
| tenant3 | 2014-01-01 |    100 |
| tenant3 | 2014-01-02 |   NULL |
| tenant3 | 2014-01-03 |    100 |
| tenant3 | 2014-01-04 |   NULL |
| tenant3 | 2014-01-05 |    100 |