6 skills.
Use when asked to write or debug MariaDB-specific SQL, choose a storage engine, or explain where MariaDB diverges from MySQL (syntax it added, features it dropped, replication/compatibility gaps) — independent of any specific ORM or client library. For syntax and behavior MariaDB shares with MySQL, see mysql-database.
Use when asked to write or debug T-SQL for Microsoft SQL Server, choose an index or isolation level, configure or tune a SQL Server instance, or explain SQL Server-specific features (T-SQL extensions, the query optimizer, Always On/replication) — independent of any specific driver or ORM.
Use when asked to write or debug MySQL-specific SQL, choose a storage engine or index type, configure or tune a MySQL/MariaDB instance, or explain MySQL-specific behavior (InnoDB locking, replication, the SQL-mode/strict-mode differences from standard SQL) — independent of any specific ORM or client library.
Use when asked to write or debug PL/SQL or Oracle-specific SQL, choose an index or partitioning strategy, configure or tune an Oracle Database instance, or explain Oracle-specific features (sequences, PL/SQL packages, MVCC via undo, RAC) — independent of any specific driver or ORM.
Use when asked to write or debug PostgreSQL-specific SQL, choose a data type or index type, configure or tune a Postgres instance, or explain PostgreSQL-specific features (JSONB, CTEs, window functions, extensions, MVCC/vacuum) — independent of any specific ORM or client library.
Use when asked to write or debug SQLite-specific SQL, understand its dynamic/manifest typing, configure WAL mode or concurrency behavior, or decide whether SQLite fits a given use case — independent of any specific driver or ORM.