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Interview Question of the Week #046 – How @@DATEFIRST and SET DATEFIRST Are Related?

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Server, SQL Tips and Tricks
SQL DateTime, SQL Scripts
Question: How @@DATEFIRST and SET DATEFIRST are related? Answer: The master database’s syslanguages table has a DateFirst column that defines the first day of the week for a particular language. SQL Server with US English as default language, SQL Server sets DATEFIRST to 7 (Sunday) by default. We can reset any day…
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Interview Question of the Week #045 – How to Do Case Sensitive Search?

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Server, SQL Tips and Tricks
One of my popular questions which helps me to understand lots of understanding of SQL by SQL developer. Question: How doing a case sensitive search in SQL Server? Answer: If Column1 of Table1 has following values ‘CaseSearch, casesearch, CASESEARCH, CaSeSeArCh’, following statement will return you all the four records. SELECT…
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Interview Question of the Week #044 – What is the difference of performance between SELECT and SET?

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Server, SQL Tips and Tricks
SQL Scripts
Question: What is the difference of performance between SELECT and SET? Answer: SELECT : Designed to return data. SET : Designed to assign values to local variables. While testing the performance of the following two scripts in query analyzer, interesting results are discovered. SET @foo1 = 1; SET @foo2 =…
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Interview Question of the Week #040 – Difference Between Unique Index vs Unique Constraint

Pinal Dave
SQL, SQL Interview Questions and Answers, SQL Server, SQL Tips and Tricks
SQL Index
Question: What is the difference between unique index and unique constraint? Answer: 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 is no difference between Unique Index…
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