SELECT * or SELECT Columns: When is SELECT * More Efficient?

*SELECT vs. SELECT Columns: Efficiency Redefined**

The common assumption that selecting specific columns (SELECT Columns) is always faster than using SELECT is often inaccurate. While large tables with numerous columns might present performance challenges with SELECT , several factors highlight the advantages of using SELECT *.

Index Optimization:

SELECT often leverages indexes more effectively. When retrieving multiple columns, SELECT increases the chances of utilizing existing indexes, minimizing disk I/O and boosting query speed. In contrast, selecting individual columns might bypass indexes, leading to slower query performance.

Maintaining Data Integrity:

SELECT * offers superior data consistency. Retrieving all columns ensures the application receives a consistent data structure, even if the table schema changes. This prevents application errors caused by schema modifications, a crucial advantage for frequently updated tables.

In Summary:

Despite initial perceptions, selectively retrieving columns isn't always the most efficient approach. Unless dealing with extremely wide tables where specific columns are demonstrably irrelevant, SELECT * provides better index utilization and consistent data handling, resulting in a more robust and efficient solution.

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