How to access separate database from SQL Server stored procedure - sql

Question

I am trying to run the below code but run into the error:
Multi-part Identifier could not be bound
I think it is due to trying to access a database table from a separate database but it is on the same server. Any ideas?
SELECT DISTINCT
#ActiveStudents2 = COUNT([ActivityHistory].[dbo].[tblActivityCounts].[id])
FROM
dbo.tblSchools
INNER JOIN
dbo.tblStudentSchool ON dbo.tblSchools.schoolid = dbo.tblStudentSchool.schoolid
INNER JOIN
dbo.tblStudentPersonal ON dbo.tblStudentSchool.id = dbo.tblStudentPersonal.id
WHERE
dbo.tblStudentSchool.schoolid IN (#tempschoolid)
AND tblStudentSchool.graduationyear IN (SELECT Items
FROM FN_Split(#gradyears, ','))
AND ([ActivityHistory].[dbo].[tblActivityCounts].[datetimechanged] >= #datefrom
AND [ActivityHistory].[dbo].[tblActivityCounts].[datetimechanged] <= #dateto)
The error occurs when I try to access the tblActivityCounts table in the Activity History database which is a separate database. I even try running this as the sa and it doesn't work. There aren't any spelling errors. Any help is appreciated. Thank you!

Answer 1

You are not joining on ActivityHistory table. That's why the query doesn't know from where to access tblActivityCounts table.

Answer 2

As Aleem said, you're not joining in the other table. I'd also recommend taking advantage of table aliases to make your code just a bit more readable... Makes it much easier to figure out what you were doing when you come back to it later.
Depending on how tblActivityCounts relates to the other tables, you would do something like this:
SELECT #ActiveStudents2 = COUNT(ActivityHistory.dbo.tblActivityCounts.id)
FROM dbo.tblSchools as Schools
INNER JOIN dbo.tblStudentSchool as Students
ON Schools.schoolid = Students.schoolid
INNER JOIN dbo.tblStudentPersonal as Personel
ON Students.id = Personel.id
INNER JOIN ActivityHistory.dbo.tblActivityCounts as Activity
ON Activity.studentid = Students.id -- Depending on how tblActivityCounts relates to the other tables
WHERE Students.schoolid IN (#tempschoolid)
AND tblStudentSchool.graduationyear IN (SELECT Items FROM FN_Split(#gradyears, ','))
AND Activity.datetimechanged >= #datefrom
AND Activity.datetimechanged <= #dateto

Answer 3

Your query is wrong. This line:
SELECT DISTINCT
#ActiveStudents2 =
COUNT([ActivityHistory].[dbo].[tblActivityCounts].[id])
Will retrieve all Ids from the tblActivityCounts table and count them, but has no reference in the rest of your query. You have to JOIN with this table and reference it to make your count. Also, I would recommend you use aliases.
Something like this:
SELECT DISTINCT
#ActiveStudents2 = COUNT(ah.[id])
FROM dbo.tblSchools s
INNER JOIN dbo.tblStudentSchool ss ON s.schoolid = ss.schoolid
INNER JOIN dbo.tblStudentPersonal sp ON s.id = sp.id
INNER JOIN [ActivityHistory].[dbo].[tblActivityCounts] ah ON s.acIdentifier = ah.acIdentifier
WHERE ss.schoolid IN (#tempschoolid)
AND ss.graduationyear IN (SELECT Items
FROM FN_Split(#gradyears, ','))
AND ([ActivityHistory].[dbo].[tblActivityCounts].[datetimechanged] >= #datefrom
AND [ActivityHistory].[dbo].[tblActivityCounts].[datetimechanged] <= #dateto)