问题
When attempting to do an OPENQUERY from Sybase to Microsoft SQL I run into an error:
Duplicate column names are not allowed in result sets obtained through OPENQUERY and OPENROWSET. The column name "PatientID" is a duplicate.
The query I have built joins 2 tables based on similar admissionID and patientID.
For Instance:
PatID AdmID Loc PatID AdmID Doctor
1 5 NC 1 5 Smith
2 7 SC 2 7 Johnson
The real query of course has a ton more information than just this.
Is there a good way to rename or remove one of the AdmID and PatID columns?
I attempted:
SELECT * INTO #tempTable
ALTER #tempTable
DROP COLUMN PatID
This does not work since PatID is ambiguous.
I also attempted:
SELECT firstTable.PatID as 'pID', * FROM...
This does not work either.
回答1:
You'll have to alias one of the two duplicate columns and explicitly indicate specific columns in the select at least for one of the tables (the one you've used the alias on it's column):
SELECT firstTable.PatID as 'pID', firstTable.column2, secondTable.* FROM...
Notice, I've still used a wildcard on the secondTable.
However....
I'd avoid using * wildcards altogether and try to always indicate exactly the columns you need.
回答2:
Duplicate and missing column names are allowed in result sets but not in table definitions (although given the error message, it looks like they wouldn't even be allowed in the result set for this situation anyway). Hence you cannot use the SELECT * construct if either of these things occur. You need to specify the fields so that you can control the field names as they appear in the result set.
SELECT *
INTO #TempTable
FROM OPENQUERY('SELECT tab1.Field1, tab1.Field2, tab2.Field12...');
来源：https://stackoverflow.com/questions/30327357/how-to-remove-rename-a-duplicate-column-in-sql-not-duplicate-rows