MySQL Query Analyzer

This online tool analyzes MySQL queries to diagnose performance and correctness issues. It accepts a SQL statement and optional schema context, validates syntax, and returns a structured assessment of the query's behavior under typical workloads. It is intended for DBAs, backend engineers, and data developers who want quick, reproducible feedback before deploying changes.
Core logic translates the input into an execution model using MySQL explain semantics, assessing access methods, join order, and estimated row counts to compute cost estimates and bottlenecks. It surfaces potential full table scans, suboptimal index usage, and costly joins. Advanced mode compares multiple plan variants and suggests index candidates and safe rewrites to lower cost.
Inputs include sql_query (required), database_version (optional, defaults to latest 8.x), schema_sample (optional, JSON or DDL), and query_options (optional: enable explain_analyze, max_cost). Outputs include plan_text (string), estimated_cost (number), estimated_rows (number), recommendations (array), rewritten_query (string), and a structured JSON summary for automation. It also provides a human-readable summary of findings.
Audience includes DBAs and developers who optimize OLTP and OLAP workloads. Unique value is in combining syntax validation, explain-based analysis, index recommendations, and exportable improvement paths that do not require manual explain-parsing. The tool is designed for iterative use across development, staging, and incident remediation to accelerate performance tuning.