SQL SERVER – Difference Between Unique Index vs Unique Constraint

Unique Index and Unique Constraint are the same. They achieve same goal. SQL Performance is same for both. Add Unique Constraint ALTER TABLE dbo.<tablename> ADD CONSTRAINT <namingconventionconstraint> UNIQUE NONCLUSTERED ( <columnname> ) ON [PRIMARY] Add Unique Index CREATE UNIQUE NONCLUSTERED INDEX <namingconventionconstraint> ON dbo.<tablename> ( <columnname> ) ON [PRIMARY] There…
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