SQL Server Performance Forum – Threads Archive

Warning while creating constraint!

I was trying to create a unique constraint on these fields for this table, I am getting this warning. Will this give problems in the insert/update for this table? Also, I can’t change the column name in the table. Any suggestions? ALTER TABLE wr_admin.wr_report
ADD CONSTRAINT U_WR_REPORT UNIQUE NONCLUSTERED (wr_report_name, wr_report_location, wr_report_provider_id)
Warning! The maximum key length is 900 bytes. The index ‘U_WR_REPORT’ has maximum length of 1054 bytes. For some combination of large values, the insert/update operation will fail.
Thanks, Name
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Dilli Grg (1 row(s) affected)

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Nover mind, I need to figure out the way to reduce one of the column’s length on existing table. Thanks, Name
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Dilli Grg (1 row(s) affected)

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Check this out: ms-help://MS.SQLCC.v9/MS.SQLSVR.v9.en/udb9/html/973b128d-5114-4d48-8eab-52497b47611e.htm —
Frank Kalis
Moderator
Microsoft SQL Server MVP
Webmaster:http://www.insidesql.de

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If you need the unique constraint, you’re restricted to the 900 bytes keysize for an index ! So, reducing columnsizes is the way to go. With included columns, the aim is to reduce IO to index-only access.
The included columns are not part of the key for the index.

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Thanks guys for your responses/link. Found the way to reduce coumn size at last. Thanks, Name
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Dilli Grg (1 row(s) affected)

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