> For the complete documentation index, see [llms.txt](https://docs.prestd.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.prestd.com/databases/mysql.md). # MySQL Use MySQL 8.0.19+ with pREST — native dialect from v2.5.0, MCP from v2.5.1. REST CRUD, alias schema scope, and documented gaps. MariaDB is not this adapter. **pREST** v2.5.0+ exposes **MySQL 8.0.19+** through a native dialect adapter. Set `engine = "mysql"`. An empty `engine` stays PostgreSQL. *Last updated: October 18, 2026* · **Label:** Native (MySQL 8.0.19+) MariaDB, TiDB, and Amazon Aurora MySQL are **not** this adapter. MCP (`/_mcp`) is supported from **v2.5.1**, read-only. *** ## Supported features | Capability | Status | | --------------------------------- | ------------------------------------------------------------------------------------- | | Connection | `engine = "mysql"`, or a `[[databases]]` URL starting with `mysql://` and no `engine` | | Schema discovery | supported (`information_schema`; system schemas hidden) | | CRUD | supported, with write differences below | | Filtering / ordering / pagination | supported (`LIMIT` / `OFFSET`) | | Scripts (`/_QUERIES`) | supported — `?` placeholders and backtick identifiers | | ACL / permissions | same TOML allowlist as PostgreSQL | | MCP (`/_mcp`) | supported (v2.5.1+), read-only, backticks / `?` | | pgvector / ltree / `tsquery` | unsupported operators | *** ## Connection ```toml engine = "mysql" [pg] url = "mysql://user:pass@localhost:3306/mydb" ``` Or environment variables. `PREST_DB_*` is read first, then legacy `PREST_PG_*`: ```sh export PREST_VERSION=2 export PREST_ENGINE=mysql export PREST_DB_URL='mysql://user:pass@localhost:3306/mydb' ``` `engine = "mysql"` (or `PREST_ENGINE=mysql`) is required: a root `mysql://` URL without it is ignored and pREST falls back to PostgreSQL defaults. TLS can also be set in the URL with `?tls=false`, `?tls=true`, or `?tls=skip-verify`. Port defaults to **3306** when unset. Postgres defaults (user `postgres`, database `prest`, port 5432) are not applied. A missing user or database fails startup. TLS: `disable`, `require`, or `skip-verify`. A client cert, key, or root certificate fails startup in this release. `[[databases]]` entries can set `engine = "mysql"` per alias. See [Multi-database](/get-started/multi-database.md). *** ## Paths Routes stay `/{database}/{schema}/{table}`. * `{database}` selects the pool: a registry alias, or — without a registry — `pg.database` or a name in `pg.allowed_databases` (v2.5.2). Any other name is **400** `database not registered`. * `{schema}` is the MySQL database. Without a registry it must equal `{database}` (v2.5.2); otherwise the request is **404** `schema not served by this database`. * `/databases` and `/schemas` list only served databases. * Hidden schemas: `mysql`, `information_schema`, `performance_schema`, `sys`. *** ## Registry From **v2.5.1** ([#1056](https://github.com/prest/prest/pull/1056)): * A `[[databases]]` alias serves only the database named in its `url` or `database`. Any other `{schema}` is **404** on CRUD, `/show`, and `/{alias}/{schema}` table listing. * In registry mode `/databases` returns `[{"datname": alias, "name": alias, "physical_name": database}]` instead of every database on the server. * From **v2.5.2**, `/schemas` in registry mode lists only the MySQL entries on the same host and port, not every database the login can see. * From **v2.5.2**, an entry that is unreachable at startup answers **503** `database unavailable` until it connects, instead of stopping startup. * Without a `[[databases]]` block, see [Paths](#paths): only `pg.database` and `pg.allowed_databases` are served. Before v2.5.2 the single connection served every granted database as `{schema}`. * A `[[databases]]` entry whose `url` starts with `mysql://` and has **no** `engine` is MySQL. Any other URL is not probed. Empty root `engine` stays PostgreSQL. *** ## Known limitations * **MySQL 8.0.19+.** The upsert form needs the row alias added in 8.0.19. MariaDB is out of scope. * **No SQL `RETURNING`.** Insert is followed by `SELECT *` in the same transaction. `UPDATE`/`DELETE` without `_returning` return `{"rows_affected": n}`. With `_returning`, pREST emulates the row image inside a `REPEATABLE READ` transaction. * **`Prest-Batch-Method: copy`** is a transactional multi-row `INSERT`, not `LOAD DATA`. Batch insert uses the union of keys. A missing key is SQL `DEFAULT`. * **No `FULL` join.** `INNER`, `LEFT`, `RIGHT`, and `CROSS` are generated. * **`$ilike` is `LIKE`.** Case follows the column collation. pREST does not wrap the column in `LOWER()`. * **`$all`, ltree, `$tsquery`, and `vecdist` error** with `unsupported operator`. * **Scripts** use `?` placeholders and backtick `ident`, not Postgres `$n` and double quotes. * **Connection failure** (down, refused, timed out) is **503** `{"error":"database unavailable"}` with no driver text. * **MySQL 1146, 1142, 1044, and 1049** are **404**. For 1142, 1044, and 1049 the server text is dropped because it names the account. * **`DATETIME` has no zone** (`YYYY-MM-DDTHH:MM:SS`). **`TIMESTAMP` is UTC** with `+00:00`. `DATE` is `YYYY-MM-DD`. * **`DECIMAL` / `NUMERIC` stay strings**, so `SUM` / `AVG` of an integer column is a string. Dialect matrix in the server repo: [`integration/mysql/DIFFERENCES.md`](https://github.com/prest/prest/blob/v2.5.2/integration/mysql/DIFFERENCES.md). *** ## Related * [v2.5.2 release notes](/releases/v2.5.2.md) * [v2.5.1 release notes](/releases/v2.5.1.md) * [v2.5.0 release notes](/releases/v2.5.0.md) * [Multi-database](/get-started/multi-database.md) * [MCP over HTTP](/get-started/mcp-over-http.md) * [Databases](/databases.md) * [Database roadmap](/databases/roadmap.md) * [API Reference](/api-reference.md) * [Acronyms](/readme/acronyms.md) ([MCP](/readme/acronyms.md#mcp), [REST](/readme/acronyms.md#rest))