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<!-- -->
> CREATE TABLE dbo.Something
> (
> Id bigint,
> OtherId bigint,
>
> CONSTRAINT PK_Something PRIMARY KEY (Id)
> );
> GO
>
> <pre>
> ✓
> </pre>
<!-- -->
> SELECT [name], is_nullable
> FROM sys.columns c
> WHERE
> c.[object_id] = OBJECT_ID('dbo.Something');
> GO
>
> <pre>
> name | is_nullable
> :------ | :----------
> Id | False
> OtherId | True
> </pre>
<!-- -->
> ALTER TABLE dbo.Something
> DROP CONSTRAINT PK_Something;
> GO
>
> <pre>
> ✓
> </pre>
<!-- -->
> SELECT [name], is_nullable
> FROM sys.columns c
> WHERE
> c.[object_id] = OBJECT_ID('dbo.Something');
> GO
>
> <pre>
> name | is_nullable
> :------ | :----------
> Id | False
> OtherId | True
> </pre>
*db<>fiddle [here](https://dbfiddle.uk/?rdbms=sqlserver_2019&fiddle=2ab11da3c49afa09e850ad4b3871dd6d)*
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