Create view with primary key?

Question

I create a view with following codes

SELECT
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T1' AS sno,
    YEAR(okuma_tarihi) AS Yillar,
    SUM(toplam_kullanim_T1) AS TotalUsageValue, 'T1' AS UsageType
FROM
    TblSayacOkumalari
GROUP BY
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T1', YEAR(okuma_tarihi)

UNION ALL

SELECT
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T2' AS sno,
    YEAR(okuma_tarihi) AS Yillar,
    SUM(toplam_kullanim_T2) AS TotalUsageValue, 'T2' AS UsageType
FROM
    TblSayacOkumalari
GROUP BY
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T1', YEAR(okuma_tarihi)

UNION ALL

SELECT
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T3' AS sno,
    YEAR(okuma_tarihi) AS Yillar,
    SUM(toplam_kullanim_T3) AS TotalUsageValue, 'T3' AS UsageType
FROM
    TblSayacOkumalari
GROUP BY
    CONVERT(NVARCHAR, YEAR(okuma_tarihi)) + 'T1', YEAR(okuma_tarihi)

I want to define CONVERT(nvarchar, YEAR(okuma_tarihi)) + 'T1' AS sno as a primary key is that possible? If is this possible how can I do?

Answer 1

You cannot create a primary key on a view. In SQL Server you can create an index on a view but that is different to creating a primary key.

If you give us more information as to why you want a key on your view, perhaps we can help with that.

Answer 2

You may not be able to create a primary key (per say) but if your view is based on a table with a primary key and the key is included in the view, then the primary key will be reflected in the view also. Applications requiring a primary key may accept the view as it is the case with Lightswitch.