That's the problem with relying on system-generated names for constraints, such as primary keys.

You would think Microsoft would know better.

USE tempdb;

GO

CREATE TABLE #SystemGenerated

(

-- No constraint name specified

row_id INTEGER IDENTITY NOT NULL PRIMARY KEY

);

GO

CREATE TABLE #Explicit

(

row_id INTEGER IDENTITY NOT NULL,

-- Explicitly named constraint

CONSTRAINT [PK #Explicit row_id]

PRIMARY KEY CLUSTERED (row_id ASC)

WITH (FILLFACTOR = 100)

ON [PRIMARY]

);

GO

-- Show primary key details

SELECT constraint_name = name,

type_desc,

is_system_named,

table_schema = SCHEMA_NAME([schema_id]),

table_name = OBJECT_NAME(parent_object_id)

FROM sys.key_constraints

WHERE parent_object_id = OBJECT_ID(N'tempdb..#SystemGenerated', N'U')

OR parent_object_id = OBJECT_ID(N'tempdb..#Explicit', N'U');

GO

-- Clean up

DROP TABLE

#SystemGenerated,

#Explicit;

Paul