Read missing index DMVs with a cost filter

SQL Server records where it thinks an index would have helped. Treat these as clues, not orders.

SELECT TOP (20)
    ROUND(migs.avg_total_user_cost
        * migs.avg_user_impact
        * (migs.user_seeks + migs.user_scans), 0) AS improvement_measure,
    mid.statement AS table_name,
    mid.equality_columns,
    mid.inequality_columns,
    mid.included_columns,
    migs.user_seeks,
    migs.user_scans,
    migs.avg_total_user_cost,
    migs.avg_user_impact
FROM sys.dm_db_missing_index_groups AS mig
INNER JOIN sys.dm_db_missing_index_group_stats AS migs
    ON migs.group_handle = mig.index_group_handle
INNER JOIN sys.dm_db_missing_index_details AS mid
    ON mig.index_handle = mid.index_handle
WHERE mid.database_id = DB_ID()
ORDER BY improvement_measure DESC;

Before creating anything:

• Check for overlapping existing indexes
• Prefer consolidating similar suggestions
• Validate with actual query plans and write overhead
• Remember DMVs reset on service restart

Missing-index recommendations are a starting point for tuning — not a shopping list.