sql - Column conflicts with the type of other columns in the unpivot list

Question

Im pivoting sys.[views] into key value pairs to compare with values on another server for consistency testing. Im running into an issue which returns the error.

Msg 8167, Level 16, State 1, Line 51

The type of column "type" conflicts with the type of other columns specified in the UNPIVOT list.

Query:

SELECT
sourceUnpivoted.idServer,
sourceUnpivoted.sourceServerName,
sourceUnpivoted.name,
sourceUnpivoted.columnName,
sourceUnpivoted.columnValue
FROM (
SELECT 
CAST('1' AS VARCHAR(255)) AS idServer,
CAST('thisOne' AS VARCHAR(255)) AS sourceServerName,
CAST('theDatabase' AS VARCHAR(255)) AS sourceDatabaseName,
CAST(name AS VARCHAR(255)) AS name,
CAST(object_id AS VARCHAR(255)) AS object_id,
CAST(principal_id AS VARCHAR(255)) AS principal_id,
CAST(schema_id AS VARCHAR(255)) AS schema_id,
CAST(parent_object_id AS VARCHAR(255)) AS parent_object_id,
CAST(type AS VARCHAR(255)) AS type,
CAST(type_desc AS VARCHAR(255)) AS type_desc,
CAST(create_date AS VARCHAR(255)) AS create_date,
CAST(lock_escalation_desc AS VARCHAR(255)) AS lock_escalation_desc
...
FROM noc_test.dbo.stage_sysTables
) AS databaseTables
UNPIVOT (
columnValue FOR columnName IN (
object_id,
principal_id,
schema_id,
parent_object_id,
type,
type_desc,
create_date,
lock_escalation_desc
) 
) AS sourceUnpivoted

Why does this not like [type],[type_desc],[lock_escalation_desc] ??? Ive also tried CONVERT(VARCHAR(255),type) AS type

Answer 1

It's actually a collation issue. I can resolve it by changing these lines:

CAST([type] collate database_default AS VARCHAR(255)) AS [type], 
CAST(type_desc collate database_default AS VARCHAR(255)) AS type_desc, 
CAST(create_date AS VARCHAR(255)) AS create_date, 
CAST(lock_escalation_desc collate database_default AS VARCHAR(255)) AS lock_escalation_desc 

The specific issue is that name is collated as Latin1_General_CI_AS, whereas the other 3 columns you mentioned are collated as Latin1_General_CI_AS_KS_WS (At least, on my machine, I'm not sure what it would be like on a server/database with different default collation).