Question

I have a table which includes an identity column but i cant remove the identity property.

Is there a way to disable it? Or a way to make a copy of the entire table without identity property?

Answer 1

Note that you may not be able to drop the column if it referenced by a clustered index, and you can’t drop all clustered indexes for a table because SqlAzure tables must always have a clustered index.

This means that you may have to jump through the following hoops (for at least your last clustered index, which may well be your primary key):

• rename your clustered index
• create a temp version of the table (with a new clustered index)
• copy the data from the current table
• drop the current table
• rename the temp table to the current name

This roughly looks like this:

-- Rename clustered index
EXECUTE sp_rename N'PK_My_Current_PK', N'PK_My_Current_PK_OLD',  'OBJECT'

-- If you have any FK constraints on the table, then drop them
ALTER TABLE dbo.MyTable DROP CONSTRAINT FK_My_Foreign_Key

-- Create the new version of your table - because this is SQLAzure it must have a clustered index
CREATE TABLE dbo.tmp_MyTable (
    MyID int NOT NULL,
    CONSTRAINT PK_My_Current_PK PRIMARY KEY CLUSTERED (MyID)
)

-- Copy the data into the temp table from the old table
INSERT INTO dbo.tmp_MyTable (MyID)
    SELECT MyID FROM dbo.MyTable 

-- Drop the old table 
DROP TABLE dbo.MyTable 

-- Rename the new table
EXECUTE sp_rename N'tmp_MyTable', N'MyTable', 'OBJECT' 

-- Recreate any foreign key constraints
ALTER TABLE dbo.MyTable WITH CHECK ADD FK_My_Foreign_Key FOREIGN KEY (MyID)
    REFERENCES dbo.MyForeignTable (MyID)

Hope that helps

A

Edit: As @PhilBolduc pointed out SqlAzure tables require a clustered index, not a primary key. I’ve amended the terminology above accordingly – the principle of the answer still remains.