SQL Database Concepts Question:
Download Job Interview Questions and Answers PDF
Do you know what is difference between Index Seek vs. Index Scan?
Answer:
Index Seek and Index Scan are operation for query tuning in execution plans.
Table Scan scans every record of the table. So the cost of proportional is the number of rows of that table.
The Index Scan is preferred only when the table is small.
Index Seek only touches the rows which qualify and the pages that contain that qualifying rows, so the cost of proportional is the number of qualifying rows and pages instead of the number of rows in the table.
Index seek is preferred for highly sensitive queries.
Table Scan scans every record of the table. So the cost of proportional is the number of rows of that table.
The Index Scan is preferred only when the table is small.
Index Seek only touches the rows which qualify and the pages that contain that qualifying rows, so the cost of proportional is the number of qualifying rows and pages instead of the number of rows in the table.
Index seek is preferred for highly sensitive queries.
Download Basic SQL Server Interview Questions And Answers
PDF
| Previous Question | Next Question |
| Explain what is lock escalation? | Explain what is Public Role in SQL Server? |