feat: MySQL support via the pymysql and asyncmy drivers

.changes/unreleased/Added-20260813-120000.yaml

@@ -0,0 +1,6 @@
+kind: Added
+body: 'MySQL support: the new `sql_driver` values `asyncmy` and `pymysql` generate code for [asyncmy](https://pypi.org/project/asyncmy/) (asyncio) and [PyMySQL](https://pypi.org/project/PyMySQL/) (synchronous), using `engine: "mysql"` and the same `?` placeholders as the SQLite drivers - the plugin rewrites them to the drivers'' pyformat `%s` at generation time. Inline `ENUM` (and `SET`) columns generate `enums.py` classes, `tinyint(1)` maps to `bool`, `time` to `datetime.timedelta`, and returned `json` columns stay `str` like on every other driver. `:execlastid` returns `cursor.lastrowid` (`None` when nothing was inserted); `:copyfrom` stays PostgreSQL-only. Reused parameters (`sqlc.arg` or `sqlc.slice` used at several sites) merge into one function argument even though MySQL binds every occurrence separately.'
+time: 2026-08-13T12:00:00.0000000Z
+custom:
+    Author: Rayakame
+    PR: "248"

.changes/unreleased/Fixed-20260813-120000.yaml

@@ -0,0 +1,6 @@
+kind: Fixed
+body: 'With `omit_unused_models: true`, an enum referenced only through an overridden column no longer breaks generation in either direction: an overridden enum parameter kept its `enums.X(...)` conversion while the class was filtered away (a `NameError` at import), and an enum used only by overridden return columns was retained as a dead `enums.py` nothing imports.'
+time: 2026-08-13T12:00:00.0000000Z
+custom:
+    Author: Rayakame
+    PR: "248"

.changes/unreleased/Fixed-20260813-120001.yaml

@@ -0,0 +1,6 @@
+kind: Fixed
+body: 'Query modules whose only queries return whole model rows (no `:many`) no longer import the row''s column-type modules (`datetime`, `decimal`, ...) into their `TYPE_CHECKING` block: nothing in such a module spells those types, and ruff flagged the imports as unused on generated output.'
+time: 2026-08-13T12:00:01.0000000Z
+custom:
+    Author: Rayakame
+    PR: "248"

.github/workflows/ci.yml

@@ -32,6 +32,18 @@ jobs:
           --health-interval=10s
           --health-timeout=5s
           --health-retries=5
+      mysql:
+        image: mysql:9
+        env:
+          MYSQL_ROOT_PASSWORD: root
+          MYSQL_DATABASE: testdb
+        ports:
+          - 3306/tcp              # host-port is picked automatically
+        options: >-
+          --health-cmd="mysqladmin ping -h 127.0.0.1 -uroot -proot"
+          --health-interval=10s
+          --health-timeout=5s
+          --health-retries=10
 
     strategy:
       fail-fast: false
@@ -54,6 +66,7 @@ jobs:
         env:
           # GitHub tells you which host-port was assigned via the `job.services` context
           POSTGRES_URI: postgres://postgres:postgres@localhost:${{ job.services.postgres.ports['5432'] }}/testdb
+          MYSQL_URI: mysql://root:root@localhost:${{ job.services.mysql.ports['3306'] }}/testdb
         run: |
           uv run nox -s pytest -- --coverage
 
@@ -310,6 +323,54 @@ jobs:
         run: |
           uv run nox -s turso_async_check
 
+  pymysql:
+    runs-on: ubuntu-latest
+    name: "Run pymysql check via nox"
+    permissions:
+      contents: read
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+      - name: Install uv
+        uses: astral-sh/setup-uv@ae62891fec2bb8e7d6c99fc78c9fec3a63790f8d # v10.0.0
+        with:
+          version: "0.12.3"
+          python-version: "3.13"
+
+      - name: Install sqlc
+        uses: sqlc-dev/setup-sqlc@bac53b7fb28c039a6c7f5736fd1e89744021bdd6 # v5
+        with:
+          sqlc-version: '1.31.1'
+
+      - name: Run sqlc verify via nox
+        run: |
+          uv run nox -s pymysql_check
+
+  asyncmy:
+    runs-on: ubuntu-latest
+    name: "Run asyncmy check via nox"
+    permissions:
+      contents: read
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+        with:
+          persist-credentials: false
+      - name: Install uv
+        uses: astral-sh/setup-uv@ae62891fec2bb8e7d6c99fc78c9fec3a63790f8d # v10.0.0
+        with:
+          version: "0.12.3"
+          python-version: "3.13"
+
+      - name: Install sqlc
+        uses: sqlc-dev/setup-sqlc@bac53b7fb28c039a6c7f5736fd1e89744021bdd6 # v5
+        with:
+          sqlc-version: '1.31.1'
+
+      - name: Run sqlc verify via nox
+        run: |
+          uv run nox -s asyncmy_check
+
   go-test:
     runs-on: ubuntu-latest
     name: "Run go tests"
@@ -386,7 +447,7 @@ jobs:
           retention-days: 30
 
   ci-done:
-    needs: [test, upload-coverage, asyncpg, psycopg-async, psycopg-sync, aiosqlite, sqlite3, turso-sync, turso-async, pyright, ruff, go-test, go-lint, test-build]
+    needs: [test, upload-coverage, asyncpg, psycopg-async, psycopg-sync, aiosqlite, sqlite3, turso-sync, turso-async, pymysql, asyncmy, pyright, ruff, go-test, go-lint, test-build]
     if: always() && !cancelled()
 
     runs-on: ubuntu-latest

.golangci.yml

@@ -115,6 +115,7 @@ linters:
         - '.*/internal/model\.QueryValue$'
         - '.*/internal/model\.Column$'
         - '.*/internal/render\.importSpec$'
+        - '.*/internal/driver\.placeholderStyle$'
         - '.*/plugin\.Identifier$'
       allow-empty: true
     tagliatelle:

CLAUDE.md

@@ -31,10 +31,11 @@ A sqlc WASM plugin written in Go that generates Python database code (models +
 query functions + enums) from SQL. The plugin is compiled to `wasip1/wasm` and
 executed by `sqlc generate`. Supported Python drivers: `asyncpg`,
 `psycopg_async`, `psycopg_sync` (PostgreSQL engine); `aiosqlite`, `sqlite3`,
-`turso_async`, `turso_sync` (SQLite engine; turso is pyturso, experimental).
+`turso_async`, `turso_sync` (SQLite engine; turso is pyturso, experimental);
+`pymysql`, `asyncmy` (MySQL engine).
 Model types: `dataclass`, `attrs`, `msgspec`, `pydantic`. Command support
 differs by family: `:copyfrom` is postgres-only, `:execlastid` is
-sqlite/turso-only, `:batch*` is unsupported everywhere.
+sqlite/turso/mysql-only, `:batch*` is unsupported everywhere.
 
 Generated code targets Python 3.12+ (PEP 695 type aliases and generics,
 `enum.StrEnum`). Generated output must be deterministic and byte-identical
@@ -82,7 +83,7 @@ Python tooling is uv + nox. One-time setup: `uv sync --group dev`. Requires
 uv run nox                    # all default sessions
 uv run nox -s asyncpg         # regenerate test/driver_asyncpg via sqlc, then pyright + ruff on it
                               # (one session per driver: asyncpg, psycopg_async, psycopg_sync,
-                              #  aiosqlite, sqlite3, turso_sync, turso_async)
+                              #  aiosqlite, sqlite3, turso_sync, turso_async, pymysql, asyncmy)
 uv run nox -s asyncpg_check   # `sqlc diff` variant: verifies committed generated code is up to date
                               # (CI uses these; every driver has a *_check session)
 uv run nox -s pyright ruff    # type-check / lint the test suite itself
@@ -92,12 +93,14 @@ uv run nox -s pytest          # runtime tests (needs postgres, see below)
 Extra pytest args pass through after `--`, e.g.
 `uv run nox -s pytest -- test/driver_asyncpg/msgspec/test_msgspec_classes.py -k test_name`.
 
-pytest needs a local PostgreSQL, configured via the `POSTGRES_URI` env var
-(default `postgresql://root:187187@localhost:5432/root`). CONTRIBUTING.md has
-a `docker run` one-liner for it.
+pytest needs a local PostgreSQL (`POSTGRES_URI`, default
+`postgresql://root:187187@localhost:5432/root`) AND a local MySQL
+(`MYSQL_URI`, default `mysql://root:187187@localhost:3306/root`); the
+session-end cleanup connects to both unconditionally. CONTRIBUTING.md has
+`docker run` one-liners for both.
 
 The full verification loop after a generator change: `go build ./...` ->
-rebuild wasm -> `uv run nox` -> the seven `*_check` sessions -> commit the
+rebuild wasm -> `uv run nox` -> the nine `*_check` sessions -> commit the
 regenerated fixtures together with the Go change (when told to commit).
 
 ### Changelog
@@ -117,25 +120,30 @@ generation pipeline lives in `internal/handler.go`:
    referenced by overrides; they resolve before override parsing (the override
    inherits the converter's py_type).
 2. **`internal/types`** - engine-specific SQL-type -> Python-type mapping
-   (`postgresql.go`, `sqlite.go`), selected by `GetTypeConversionFunc(engine)`.
+   (`postgresql.go`, `sqlite.go`, `mysql.go`), selected by
+   `GetTypeConversionFunc(engine)`.
 3. **`internal/transform`** - turns the sqlc catalog/queries into the IR:
    `BuildEnums()`, `BuildTables()`, `BuildQueries(tables)`,
    `FilterUnusedModels()`. `type.go` builds `PyType` and normalizes
    `SQLType` (lowercased once here; every downstream consumer relies on it).
-   `psycopg_sql.go` rewrites `$N` placeholders to psycopg's `%(pN)s` at IR
-   build time (a small PostgreSQL lexer: skips strings, dollar quotes, quoted
-   identifiers, nested comments; doubles literal `%`). `plainParams`
-   pre-reserves every local the driver bodies emit (`conn`/`self`, `sql` for
-   slice queries, psycopg's `sql_params`/`cur`/`row`/`_decode_hook`); a new
-   local in a driver body needs a matching seed or a param can shadow it.
+   `psycopg_sql.go` and `mysql_sql.go` rewrite placeholders at IR build time
+   (psycopg: `$N` -> `%(pN)s`; MySQL: `?` -> `%s` with `%` doubled - small
+   SQL lexers matching each engine's rules). `plainParams` pre-reserves
+   every local the driver bodies emit (`conn`/`self`, `sql` for slice
+   queries, psycopg's and MySQL's `sql_params`/`cur`/`row`/`_decode_hook`);
+   a new local in a driver body needs a matching seed or a param can shadow
+   it. It also merges MySQL's per-occurrence duplicates of reused NAMED
+   parameters (`IsNamedParam`; the `Repeated` flag keeps their binding
+   slots) - bare `?` params that share a column name stay distinct.
 4. **`internal/model`** - the IR structs (`Enum`, `Table`, `Query`, `PyType`,
    ...) plus naming logic: initialisms, table-name singularization
    (jinzhu/inflection; exclusions match bare AND schema-qualified names),
    Python reserved-word escaping (`reserved.go`), and `DedupName`.
-5. **`internal/driver`** - the `Driver` interface (`driver.go`) with four
+5. **`internal/driver`** - the `Driver` interface (`driver.go`) with five
    implementations: `asyncpg.go`; `psycopg.go` for BOTH psycopg flavors
    (parameterized by an async flag); `sqlite_base.go` for BOTH sqlite drivers
-   (module name + async flag); `turso.go` for BOTH turso flavors. A driver
+   (module name + async flag); `turso.go` for BOTH turso flavors;
+   `mysql_base.go` for BOTH MySQL drivers (module name + async flag). A driver
    knows which query commands it supports and emits query function bodies and
    the `QueryResults` class. `conversion.go` holds the asyncpg conversion set
    and the ordered sqlite adapter/converter spec table; adapters are
@@ -180,6 +188,10 @@ buffer is emitted as an extra output file.
   emits only what that module needs (params -> adapters, non-overridden
   returns -> converters). psycopg's loader registration follows the same
   policy (returned json/jsonb types only).
+- The MySQL drivers interpolate pyformat placeholders client-side: rewritten
+  SQL constants carry `%s`/`%%`, and the slice-expansion/placeholder-scanner
+  machinery in `internal/driver/common.go` must lex them exactly like the
+  rewriter emitted them.
 - `speedups: true` swaps date/datetime decoding to `ciso8601` (sqlite
   converter bodies, turso inline decodes); the import resolver tracks which
   variant is emitted.

CONTRIBUTING.md

@@ -14,7 +14,7 @@ that you should follow to ensure that your contribution is at its best.
   The easiest way to get exactly that version without a Go toolchain is
   [sqlc-bin](https://pypi.org/project/sqlc-bin/), whose package version tracks the
   sqlc version: `uv tool install "sqlc-bin==1.31.1"`.
-- **Docker** (or a local PostgreSQL) - only needed for the runtime tests.
+- **Docker** (or a local PostgreSQL plus a local MySQL) - only needed for the runtime tests.
 
 One-time setup for the Python tooling:
 
@@ -67,14 +67,15 @@ sessions run with `uv run nox -s name1 name2`:
 
 | Session                                             | What it does                                                                           |
 |-----------------------------------------------------|----------------------------------------------------------------------------------------|
-| `asyncpg`, `psycopg_async`, `psycopg_sync`, `sqlite3`, `aiosqlite`, `turso_sync`, `turso_async` | Regenerate the driver's test fixtures via sqlc, then pyright + ruff |
+| `asyncpg`, `psycopg_async`, `psycopg_sync`, `sqlite3`, `aiosqlite`, `pymysql`, `asyncmy`, `turso_sync`, `turso_async` | Regenerate the driver's test fixtures via sqlc, then pyright + ruff |
 | the `_check` variants of the driver sessions | `sqlc diff` variant: verify the committed generated code is up to date (CI uses these) |
 | `pyright`                                           | Type-check the repository                                                              |
 | `ruff_check`                                        | Non-mutating format + lint check (the CI gate)                                         |
 | `ruff`, `ruff_format`                               | Format and auto-fix the repository - these sessions rewrite files                      |
 | `pytest`                                            | Runtime tests against real databases                                                   |
 
-The `pytest` session needs a local PostgreSQL. The connection URI is read from the
+The `pytest` session needs BOTH a local PostgreSQL and a local MySQL - the
+session-end cleanup connects to each unconditionally. The connection URI is read from the
 `POSTGRES_URI` environment variable and defaults to
 `postgresql://root:187187@localhost:5432/root`; set the variable only if your instance
 differs from that. To start a matching instance with docker, run
@@ -88,11 +89,23 @@ docker run --rm --name sqlc-gen-better-python-postgres \
   -d postgres
 ```
 
-and stop it (after running the tests) with the command below; `--rm` removes the container
-on stop, so the `docker run` command above can be reused as is next time.
+It also needs a local MySQL for the `pymysql` and `asyncmy` suites, read from
+`MYSQL_URI` with the default `mysql://root:187187@localhost:3306/root`:
+
+```bash
+docker run --rm --name sqlc-gen-better-python-mysql \
+  -e MYSQL_ROOT_PASSWORD=187187 \
+  -e MYSQL_DATABASE=root \
+  -p 3306:3306 \
+  -d mysql:9
+```
+
+Stop the containers (after running the tests) with the commands below; `--rm` removes a
+container on stop, so the `docker run` commands above can be reused as is next time.
 
 ```bash
 docker stop sqlc-gen-better-python-postgres
+docker stop sqlc-gen-better-python-mysql
 ```
 
 Extra pytest arguments pass through after `--`, e.g.
@@ -103,7 +116,7 @@ Extra pytest arguments pass through after `--`, e.g.
 1. Change the Go code and run `make tests` / `make lint`.
 2. Rebuild the WASM plugin (see above).
 3. `uv run nox` - regenerates the fixtures and runs every check on them. The default
-   sessions include `pytest`, so have the PostgreSQL from the section above running.
+   sessions include `pytest`, so have the PostgreSQL and MySQL from the section above running.
    The `_check` sessions are not needed locally: they verify committed fixtures
    against a fresh regeneration, which is what CI does with the files you commit.
 4. If your change affects generated output, add coverage: a query/schema case in the test matrix

README.md

@@ -46,9 +46,10 @@ Questions or feedback? Join the [Discord](https://discord.gg/hikari).
 
 - **Four model types** - `dataclass`, `attrs`, `msgspec`, or `pydantic`
   ([docs](https://sqlc-gen-better-python.rayakame.dev/docs/guide/model-types/)).
-- **Seven drivers** - `asyncpg`, `psycopg_async`, and `psycopg_sync` for
-  PostgreSQL, `aiosqlite` and `sqlite3` for SQLite, plus experimental
-  `turso_async` and `turso_sync` for [Turso](https://github.com/tursodatabase/turso)
+- **Nine drivers** - `asyncpg`, `psycopg_async`, and `psycopg_sync` for
+  PostgreSQL, `aiosqlite` and `sqlite3` for SQLite, `asyncmy` and `pymysql`
+  for MySQL, plus experimental `turso_async` and `turso_sync` for
+  [Turso](https://github.com/tursodatabase/turso)
   ([docs](https://sqlc-gen-better-python.rayakame.dev/docs/guide/drivers/)).
 - **Typed query functions** - one module per query file, one function per query
   ([docs](https://sqlc-gen-better-python.rayakame.dev/docs/guide/writing-queries/)).

docs/content/_index.md

@@ -1,7 +1,7 @@
 ---
 title: sqlc-gen-better-python
 description: >-
-  A sqlc plugin that generates type-safe Python from SQL: dataclass, attrs, msgspec, or pydantic models plus fully typed query functions for asyncpg, psycopg, sqlite3, aiosqlite, and turso.
+  A sqlc plugin that generates type-safe Python from SQL: dataclass, attrs, msgspec, or pydantic models plus fully typed query functions for asyncpg, psycopg, sqlite3, aiosqlite, asyncmy, pymysql, and turso.
 layout: hextra-home
 ---
 
@@ -36,9 +36,9 @@ layout: hextra-home
     subtitle="Generate dataclass, attrs, msgspec, or pydantic models - pick per codegen block."
   >}}
   {{< hextra/feature-card
-    title="Seven drivers"
+    title="Nine drivers"
     link="docs/guide/drivers"
-    subtitle="asyncpg and psycopg for PostgreSQL, aiosqlite and sqlite3 for SQLite, and experimental turso support."
+    subtitle="asyncpg and psycopg for PostgreSQL, aiosqlite and sqlite3 for SQLite, asyncmy and pymysql for MySQL, and experimental turso support."
   >}}
   {{< hextra/feature-card
     title="Strictly typed output"