Index Issues

Multiple indexes exist on the same table covering the same columns. Duplicate indexes waste storage and slow down writes without providing additional query benefits.

A table uses an integer (4-byte) primary key that may exhaust available IDs. For high-volume tables, this can cause application failures when IDs run out.

An index that failed to build completely and is marked as invalid. Invalid indexes are not used by queries but still consume resources.

A foreign key constraint exists without an index on the referencing columns. This causes full table scans when deleting or updating parent rows.

An index that has never been scanned since statistics were last reset. Unused indexes waste disk space and slow down write operations.