Run safe read-only queries against MySQL or PostgreSQL for data inspection, reporting, and troubleshooting. Use when the user asks to read tables, inspect schema, count rows, sample data, or export query results without modifying data.

针对 MySQL 或 PostgreSQL 执行安全的只读查询，用于数据检查、报表生成和故障排查。当用户需要读取表、检查表结构、统计行数、采样数据或导出查询结果但不修改数据时使用。