ALTER TABLE SWITCH statement failed because column '%.*ls' has data type %s in source table '%.*ls' which is different from its type %s in target table '%.*ls'.

Error Message:
Msg 4944, Level 16, State 1, Line 1
ALTER TABLE SWITCH statement failed because column '%.*ls' has data type %s in source table '%.*ls' which is different from its type %s in target table '%.*ls'.

Severity level:
16.

Description:
This error message appears when you try to execute an ALTER TABLE SWITCH command, for which column(s) in the source and table table have different datatypes.

Consequences:
The T-SQL statement can be parsed, but causes the error at runtime.

Resolution:
Errors of the Severity Level 16 are generated by the user and are corrigible by the user. The statement cannot be executed this way. All column(s) in the source and target table must have the same datatype.

Versions:
This error message was introduced with SQL Server 2005.

Example(s):
USE Pubs
GO
CREATE PARTITION FUNCTION myPartFunction (int)
    AS RANGE LEFT FOR VALUES (1, 10, 100);
GO

CREATE PARTITION SCHEME myPartScheme
    AS PARTITION myPartFunction
   ALL TO ([PRIMARY]);
GO

CREATE TABLE myPartTable
(
 c1 int
)
ON myPartScheme (c1);

GO
CREATE TABLE myNonPartTable
(
 c1 bigint
)
ON [PRIMARY];
GO
ALTER TABLE myPartTable SWITCH PARTITION 1 TO dbo.myNonPartTable ;
GO

DROP TABLE myNonPartTable, myPartTable;
DROP PARTITION SCHEME myPartScheme;
DROP PARTITION FUNCTION myPartFunction;

Remarks:
In the above example we try to execute an ALTER TABLE SWITCH command. Because the columns in the source and target table do haev different datatypes, the error is raised.