mysql-database

MySQL Database — Skill

Use this skill when working with MySQL or MariaDB databases in Delphi projects via FireDAC.

When to Use

• When configuring FireDAC connection with MySQL or MariaDB
• When creating tables, stored procedures, functions, triggers and views
• When implementing Repositories with FireDAC + MySQL
• When working with native JSON (MySQL 5.7+), Full-Text Search, Partitioning
• When planning schema migrations (versioned scripts)
• When developing web applications with MySQL backend

Quick Reference

Minimum connection:

FConnection.DriverName := 'MySQL';
FConnection.Params.Values['Server'] := 'localhost';
FConnection.Params.Values['Port'] := '3306';
FConnection.Params.Database := 'meubanco';
FConnection.Params.UserName := 'root';
FConnection.Params.Password := 'senha';
FConnection.Params.Values['CharacterSet'] := 'utf8mb4';  //NEVER 'utf8' (only 3 bytes!)
FConnection.TxOptions.Isolation := xiReadCommitted;

Golden rules: utf8mb4 always (never utf8), MySQL has no RETURNING — use LAST_INSERT_ID(), always ENGINE=InnoDB (never MyISAM in new tables), parameterized queries only. Full details and code for each are in the reference files below — read the one that matches the task at hand rather than guessing.

references/

Read only the file(s) relevant to the current task — this skill file is intentionally short; the depth lives in these files.

• connection-and-types.md — supported MySQL/MariaDB versions, FireDAC connection setup (driver link, pooling, SSL/TLS), MySQL ↔ Delphi data type mapping.
• schema-and-migrations.md — AUTO_INCREMENT + LAST_INSERT_ID(), triggers, InnoDB vs MyISAM, partitioning, migration scripts, and runtime schema-existence checks from Delphi.
• querying.md — UPSERT (ON DUPLICATE KEY UPDATE), native JSON, Full-Text Search, stored procedures/functions, ENUM/SET, CTEs and Window Functions (8.0+), UUID primary keys.
• transactions-and-ops.md — transactions/isolation levels, SAVEPOINT, error handling (EFDDBEngineException/MySQL error codes), MySQL-vs-Firebird-vs-PostgreSQL differences, anti-patterns, and the pre-flight checklist.