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Interview Question of the Week #021 - Difference Between Index Seek and Index Scan (Table Scan)

Question: What is the difference between Index Seek and Index Scan?

Answer: Index Scan retrieves all the rows from the table. Index Seek retrieves selective rows from the table. 244 more words

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Interview Question of the Week #020 - What is the Difference Between DISTINCT and GROUP BY?

Question: What is the Difference Between DISTINCT and GROUP BY?

Answer: A DISTINCT and GROUP BY usually generate the same query plan, so performance should be the same across both query constructs. 117 more words

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Interview Question of the Week #019 - How to Reset Identity of Table

Here is the question which I received in email:

Question: I have a table which has an identity column. I have recently deleted old and archive it to another place. 126 more words

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Interview Question of the Week #018 - Script to Remove Special Characters - Script to Parse Alpha Numerics

If you ask me – there are certain questions not appropriate for an interview as they are often very subjective. There are some questions, which really do not help to identify if the candidate has the necessary skills or not. 228 more words

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Interview Question of the Week #017 - Performance Comparison of Union vs Union All

Here is what I just learned from email. One of the very prestigious organization asks one of their candidate following questions –

Question: If you have options to use Union or Union All – which one of the option will use keeping performance as a top most requirement for the query. 277 more words

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Interview Question of the Week #016 - How to Take Database Offline

Here is the question, I received in the recent conference where I was presenting on Database Technology.

Question: What does it mean by Taking Database Offline and How to do it? 101 more words

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Interview Question of the Week #014 - How to DELETE Duplicate Rows

Here is another very common question I often received, which candidates face in the interview.

Question: How to delete duplicate rows in SQL Server (considering there is an identity column in table)? 81 more words

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