Indexes for Database Performance: To Index or Not to Index?

Indexes for Enhanced Database Performance: A Guide to Dos and Don'ts

Improving database performance through indexes is an essential optimization technique. Here are some key guidelines to follow:

Dos:

• Do create indexes on columns frequently used in query where clauses. This allows the database to quickly locate rows matching specific criteria.
• Do use multicolumn indexes for queries that sort or filter multiple columns. This reduces the need for multiple index lookups.
• Do consider using partial indexes to exclude rows with specific values, reducing index size and improving performance.
• Do keep table statistics up to date. Outdated statistics can lead to suboptimal index usage.

Don'ts:

• Don't create indexes unnecessarily. Each index slows down write operations, so only create indexes when genuinely needed.
• Don't create indexes on columns that are rarely used in queries. This adds unnecessary overhead without significant performance improvement.
• Don't create duplicate indexes. If an index exists for a specific target, creating a second index with the same criteria will not further enhance performance.
• Don't use indexes for boolean fields that divide the table into nearly equal subsets. Such indexes will not significantly improve query performance.

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