How to use CTE with dynamic query pivot? - sql

Question

I am using SQL Server 2008 R2
First I needed to break the dates (start date and end date) into every day from table1 which I did with recursive CTE.
DECLARE #maxdate DATETIME = (SELECT Max([EndDate]) FROM table1);
WITH CTE_DateToDays
AS (SELECT StartDate as Dates
FROM table1
UNION ALL
SELECT Dateadd(day, 1, Dates)
FROM CTE_DateToDays
WHERE Dates < #maxdate)
Select Dates from CTE_DateToDays;
Then I wanted to convert rows into columns from table2. Which I did with dynamic pivot, as I did not know the number of columns.
DECLARE #TimeBandColms AS NVARCHAR(MAX);
Select #TimeBandColms = STUFF((SELECT ',' + QUOTENAME(t.TimeBandName)
from table2 t
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'');
Select #TimeBandColms
from
(
SELECT t.TimeBandID,t.TimeBandName
FROM
table2 t
) x
pivot
(
MAX(TimeBandID)
for TimeBandName in (" + #TimeBandColms + N")
) piv;
Now here I am stuck whenever I combine these two things, sometimes the result set is not what I want or sometimes error with 'Invalid column name' or 'Multi-part identifier could not be bound'.
NOTE
Table1 and Table2 are different tables with nothing in common like key or id.
I have tried many things like union or different approach, but couldn't solve my problem.
Sorry if I am not more specific, but I am new to this pivot, stuff, and CTE.
I really need your help.
The result set which I want is something like this...
Here is my attempt.
DECLARE #TimeBandColms AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
select #TimeBandColms = STUFF((SELECT ',' + QUOTENAME(t.TimeBandName)
from table2 t
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'');
set #query = 'DECLARE #maxdate DATETIME = (SELECT Max([EndDate]) FROM
table1);
WITH CTE_DateToDays
AS (SELECT StartDate as Dates
FROM table1
UNION ALL
SELECT Dateadd(day, 1, Dates)
FROM CTE_DateToDays
WHERE Dates < #maxdate)'
Set #query += N'SELECT ' + #TimeBandColms + N' from
(
SELECT CTE_DateToDays.Dates, t.TimeBandID,t.TimeBandName
FROM CTE_DateToDays,
table2 t
) x
pivot
(
max(Dates)
for TimeBandName in (' + #TimeBandColms + N')
) piv;'
exec (#query);

Answer 1

You can try this.
DECLARE #TimeBandColms AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
select #TimeBandColms = STUFF((SELECT ',' + QUOTENAME(t.TimeBandName)
from table2 t
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'');
set #query = 'DECLARE #maxdate DATETIME = (SELECT Max([EndDate]) FROM
table1);
WITH CTE_DateToDays
AS (SELECT StartDate as Dates
FROM table1
UNION ALL
SELECT Dateadd(day, 1, Dates)
FROM CTE_DateToDays
WHERE Dates < #maxdate)'
Set #query += N'SELECT Dates, ' + #TimeBandColms + N' from
(
SELECT CTE_DateToDays.Dates, t.TimeBandID, t.TimeBandName
FROM CTE_DateToDays
CROSS JOIN table2 t
) x
pivot
(
count(TimeBandID)
for TimeBandName in (' + #TimeBandColms + N')
) piv;'
exec (#query);