MySQL Queries Doing Full Table Scans

Ranks queries that scan whole tables without an index by total latency. The fastest way to find missing indexes.

#full-table-scan#sys-schema#missing-index

mysql · sql

SELECT db, LEFT(query, 150) AS query, exec_count,
       sys.format_time(total_latency) AS total_latency,
       no_index_used_count, rows_examined_avg
FROM sys.x$statements_with_full_table_scans
ORDER BY total_latency DESC
LIMIT 20;

Operational Notes & Remediation Guidance

Verify in a staging environment prior to running in production. This is a read-only diagnostic query; it does not acquire exclusive locks.

Production Safety & Execution Standards

This script is designed for read-only diagnostics; it does not alter schema or modify data directly.
Prior to executing on production systems under high load, verify the target database version (Min. Version: 5.7).
Exercise caution with mutating actions (e.g., terminating sessions or dropping indexes) referenced in the notes section.

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