Release 3.1.1 (#550)

## Release `3.1.1`

Version bump and changelog update for release `3.1.1`.

**Changelog draft:**
* Support date arithmetic with `INTERVAL` operators
([#539](#539))
* Fix `ROLLBACK` as the first transaction of a connection
([#537](#537))
* Fix matching a foreign key reference to a unique key with a different
case
([#534](#534))
* Fix `FOUND_ROWS()` without `SQL_CALC_FOUND_ROWS`
([#533](#533))
* Fix unique keys and foreign key restore without stringified fetches
([#532](#532))
* Fix `CREATE TEMPORARY TABLE IF NOT EXISTS` and `DROP TEMPORARY TABLE`
as the first temporary table
([#524](#524))
* Fix a warning for a foreign key referencing a table with a shorter
unique key
([#523](#523))
* Fix temporary table lookup without stringified fetches and with a
different case
([#522](#522))

**Full changelog:**
v3.1.0...release/v3.1.1

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.1.1`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP, create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases),
and deploy to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.1.0 (#521)

## Release `3.1.0`

Prepares the version numbers and release notes for `3.1.0`.

**Changelog draft:**

---

**SQLite Database Integration 3.1 is here! 🎉**

This release improves **database storage and configuration** and fixes
several MySQL compatibility issues.

## What's new

Version 3.1 improves how WordPress sites store, locate, and protect
their SQLite databases. It also fixes SQL behavior and export
compatibility:

- **Randomized database paths:** The default database location is now a
randomized directory under `wp-content/database/`, recorded in
`wp-content/database/db-path.php`.
([#502](#502))
- **`DB_PATH`:** Configure the database with one full-path constant,
also available at runtime for integrations.
([#512](#512))
- **SQL compatibility:** Fix `IF()` condition evaluation and make
`TRADITIONAL` enable its component SQL modes.
([#518](#518),
[#509](#509))
- **WordPress table collations:** Default to `utf8mb4_unicode_520_ci`
for new tables created with WordPress's charset settings, improving
exports to MariaDB. Existing tables keep their recorded collation.
([#514](#514))
- **Documentation:** A new plugin README and expanded FAQ explain
database storage and secure configuration.
([#520](#520))

For more information about database paths and secure configuration, read
the [database storage
guide](https://github.com/WordPress/sqlite-database-integration/blob/trunk/packages/plugin-sqlite-database-integration/README.md#database-storage).

## Upgrading to 3.1

Upgrading an existing SQLite site is straightforward:

1. **Back up** your SQLite database.
2. **Update the plugin** to version 3.1.

Existing `.ht.sqlite` and `.ht.sqlite.php` databases move to the
randomized layout automatically unless a database file path is
explicitly configured.

To properly **secure the database**, set `DB_PATH` in `wp-config.php` to
an absolute file path outside the web root that your web server does not
expose. Its directory must be writable by PHP. Changing `DB_PATH` does
not move an existing database.

## Breaking changes

Review these changes if you use custom database settings or
integrations:

- **Database paths:** Default database files now move to randomized
paths under `wp-content/database/`. Explicitly configured file paths
stay unchanged. Integrations, including backup and migration tools, must
read `DB_PATH` after WordPress loads instead of assuming a fixed
filename.
- **Legacy constants:** `DB_DIR` and `DB_FILE` are now deprecated. They
and the previously deprecated `FQDB` and `FQDBDIR` remain supported, but
`DB_PATH` takes precedence. Conflicting values trigger warnings.
- **Absolute paths:** Relative database file and directory paths are now
rejected. `:memory:` remains available for in-memory databases.

## Thank you

Thank you to everyone who contributed, tested, and helped update
integrations.

**Changes since 3.0.2:**
[`v3.0.2...v3.1.0`](v3.0.2...v3.1.0)

---

**PR comparison:**
[`v3.0.2...release/v3.1.0`](v3.0.2...release/v3.1.0)

## Next steps

1. **Review** the release changes and changelog draft.
2. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP, create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases),
and deploy to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.0.2 (#507)

## Release `3.0.2`

Version bump and changelog update for release `3.0.2`.

**Changelog draft:**
* Fix schema reconstruction with native numeric results
([#506](#506))
* Fix lexer edge cases and string handling
([#505](#505))
* Preserve index prefix lengths and order in SHOW CREATE TABLE primary
keys
([#500](#500))
* Align savepoint handling with MySQL semantics
([#496](#496))

**Full changelog:**
v3.0.1...release/v3.0.2

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.2`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP, create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases),
and deploy to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **Bug Fixes**
  - Improved schema reconstruction when handling native numeric results.
  - Corrected lexer edge cases and string processing.
- Fixed index prefix lengths and ordering in `SHOW CREATE TABLE` output
for primary keys.
  - Improved savepoint handling to better match MySQL behavior.

- **Release**
  - Updated the SQLite integration to version 3.0.2.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Release 3.0.1 (#498)

## Release `3.0.1`

Version bump and changelog update for release `3.0.1`.

**Changelog draft:**
* Mark the plugin as compatible with WordPress 7.1
([#497](#497))
* Fix fresh multisite database setup
([#492](#492))

**Full changelog:**
v3.0.0...release/v3.0.1

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.1`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP, create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases),
and deploy to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Bug Fixes**
  - Fixed fresh multisite database setup for improved reliability.
  - Added compatibility with WordPress 7.1.

- **Chores**
  - Updated the SQLite driver and integration plugin to version 3.0.1.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Release 3.0.0 (#488)

## Release `3.0.0`

Prepares the version numbers and release notes for `3.0.0`.

**Changelog draft:**

---

**SQLite Database Integration 3 is here! 🎉**

This release introduces an **all-new SQLite database driver for
WordPress**, rebuilt from the ground up. Its purpose-built MySQL lexer,
parser, and emulation layer deliver broader compatibility, more accurate
behavior, and a stronger foundation for future improvements.

The 3.0 release spans nearly two years of work, featuring [160 pull
requests](https://github.com/WordPress/sqlite-database-integration/milestone/3?closed=1)
and 1,075 commits from 15 contributors.

## What's new

The new driver advances SQLite support for WordPress, plugins, database
tools, and other MySQL-based applications. These improvements include:

- **New SQL engine:** The pure-PHP lexer and parser provide extensive
coverage of the official MySQL grammar.
- **Broad query support:** Complex joins, subqueries, CTEs, unions, and
other advanced queries are now supported.
- **Schema emulation:** WordPress and database tools can query emulated
MySQL `INFORMATION_SCHEMA` tables.
- **Schema introspection:** `SHOW` and `DESCRIBE` statements provide
accurate MySQL-like metadata.
- **Improved data handling:** Types, casts, defaults, auto-increment,
values, and escaping better match MySQL.
- **Refined MySQL semantics:** Better emulation of SQL modes, variables,
functions, transactions, and errors.
- **Better concurrency:** Write-ahead logging and fewer locks reduce
blocking between readers and writers.
- **PDO API:** The new driver implements the PDO MySQL API, supporting
many MySQL-based tools and applications.
- **Extensive testing:** Test suites cover parsing, translation,
metadata, concurrency, PDO, and end-to-end workflows.

For more information about the new driver and its architecture, read the
[driver
announcement](https://make.wordpress.org/playground/2025/06/13/introducing-a-new-sqlite-driver-for-wordpress/).

## Modular design

The project was redesigned as a set of focused packages, separating the
core driver from its WordPress integration:

- [SQLite Database
Integration](https://github.com/WordPress/sqlite-database-integration/tree/v3.0.0/packages/plugin-sqlite-database-integration):
The **WordPress plugin** powered by MySQL on SQLite.
- [MySQL on
SQLite](https://github.com/WordPress/sqlite-database-integration/tree/v3.0.0/packages/mysql-on-sqlite):
A standalone **PDO MySQL drop-in** for running MySQL-based PHP
applications on SQLite.
- [MySQL
proxy](https://github.com/WordPress/sqlite-database-integration/tree/v3.0.0/packages/mysql-proxy)
(experimental): A **MySQL wire protocol bridge** to PDO-compatible
drivers for clients outside PHP.

This architecture opens the driver to new integrations, applications,
and development tools beyond WordPress.

## Upgrading to 3.0

Upgrading an existing SQLite site is straightforward:

1. **Back up** your SQLite database.
2. **Update the plugin** to version 3.0.

On first connection, the new driver automatically initializes its
metadata without changing your tables or content.

If you used the new driver preview, you can now delete the
`WP_SQLITE_AST_DRIVER` flag.

## Breaking changes

Most WordPress sites need no changes. Review the following if you use a
custom setup:

- **New driver:**
    - The new driver is always used. The legacy driver was removed.
    - The `WP_SQLITE_AST_DRIVER` feature flag was removed.
- **Updated SQLite version requirements:**
    - SQLite `3.37.0` or newer is required.
- The `WP_SQLITE_UNSAFE_ENABLE_UNSUPPORTED_VERSIONS` opt-in enables
limited SQLite `3.27.0`–`3.36.x` support.
- **`DB_NAME` is required:**
    - It must be defined and non-empty.
- It is used dynamically, independently of the SQLite file name and
stored metadata.
- **SQLite defaults have changed:**
- Journal mode now defaults to [`WAL`](https://sqlite.org/wal.html).
Account for `-wal` and `-shm` sidecar files.
- Synchronous mode now defaults to
[`NORMAL`](https://sqlite.org/pragma.html#pragma_synchronous) in `WAL`
mode.
- **Updated configuration constants:**
    - `DATABASE_ENGINE` was removed. Use `DB_ENGINE`.
    - `DATABASE_TYPE` is deprecated. Use `DB_ENGINE`.
    - `FQDBDIR` is deprecated. Use `DB_DIR`.
    - `FQDB` is deprecated. Use `DB_DIR` and `DB_FILE`.
- **Updated driver classes:**
    - `WP_SQLite_Driver` is deprecated. Use `WP_MySQL_On_SQLite`.
    - `WP_PDO_MySQL_On_SQLite` was replaced by `WP_MySQL_On_SQLite`.
- `WP_SQLite_Driver_Exception` was replaced by
`WP_MySQL_On_SQLite_Exception`.
- `WP_PDO_Proxy_Statement` was replaced by
`WP_MySQL_On_SQLite_Statement`.
- **Sunsetting `$GLOBALS['@pdo']`:**
- Injecting a PDO connection through `$GLOBALS['@pdo']` is no longer
supported.
- Reading `$GLOBALS['@pdo']` is deprecated. Use
`$wpdb->get_driver()->get_sqlite_pdo()`.
- **Renamed driver constructor options:**
    - `pdo` → `sqlite_pdo`.
    - `journal_mode` → `sqlite_journal_mode`.
    - `synchronous` → `sqlite_synchronous`.

## Thank you

Thank you to everyone who helped build, test, review, and improve the
new driver. Your work made this possible.

**3.0 milestone:** [160 pull
requests](https://github.com/WordPress/sqlite-database-integration/milestone/3?closed=1)
**Changes since 2.2.23:**
[`v2.2.23...v3.0.0`](v2.2.23...v3.0.0)

---

**PR comparison:**
[`v3.0.0-rc.9...release/v3.0.0`](v3.0.0-rc.9...release/v3.0.0)

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.0`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP, create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases),
and deploy to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.0.0-rc.9 (#489)

## Release `3.0.0-rc.9`

Version bump and changelog update for release `3.0.0-rc.9`.

**Changelog draft:**
* Reject invalid BIT column defaults
([#487](#487))
* Make Composer packages installable
([#486](#486))
* Remove INET_ATON WordPress dependency
([#485](#485))
* Restore database version support for older WordPress releases
([#484](#484))
* Finalize MySQL-on-SQLite 3.0 refinements
([#482](#482))
* Prefix SQLite-specific constructor options
([#481](#481))
* Unify emulated MySQL server identity
([#479](#479))
* Document the 3.0 driver API
([#477](#477))
* Expand PDO API coverage
([#471](#471))
* Refine the 3.0 API surface
([#469](#469))
* Add ANSI_QUOTES and SQL mode validation
([#452](#452))

**Full changelog:**
v3.0.0-rc.8...release/v3.0.0-rc.9

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.0-rc.9`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP and create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases).

> [!NOTE]
> This is a **pre-release**. It will not be deployed to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.0.0-rc.8 (#468)

## Release `3.0.0-rc.8`

Version bump and changelog update for release `3.0.0-rc.8`.

**Changelog draft:**
* Preserve aliases in `UPDATE JOIN` translation
([#462](#462))
* Restrict SQLite installation permissions
([#464](#464))
* Improve string escaping
([#466](#466))
* Stabilize WordPress E2E tests
([#459](#459))
* Address WordPress PHPUnit test fails: charset detection, length
validation etc
([#331](#331))
* Add Unicode support to the user-defined `REVERSE()` function
([#453](#453))
* Simplify the MySQL-on-SQLite driver API
([#449](#449))
* Add WordPress 7.0 compatibility
([#450](#450))

**Full changelog:**
v3.0.0-rc.7...release/v3.0.0-rc.8

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.0-rc.8`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP and create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases).

> [!NOTE]
> This is a **pre-release**. It will not be deployed to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.0.0-rc.7

Release 3.0.0-rc.6 (#444)

## Release `3.0.0-rc.6`

Version bump and changelog update for release `3.0.0-rc.6`.

**Changelog draft:**
* Don't take a write lock for SET statements (fixes "database is locked"
on connect)
([#443](#443))
* Add REVERSE() to user defined functions
([#434](#434))
* LALR(1) parser from official MySQL grammar
([#429](#429))

**Full changelog:**
v3.0.0-rc.5...release/v3.0.0-rc.6

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.0-rc.6`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP and create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases).

> [!NOTE]
> This is a **pre-release**. It will not be deployed to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).

Release 3.0.0-rc.5 (#441)

## Release `3.0.0-rc.5`

Version bump and changelog update for release `3.0.0-rc.5`.

**Changelog draft:**
* Default SQLite connections to WAL
([#405](#405))

**Full changelog:**
v3.0.0-rc.4...release/v3.0.0-rc.5

## Next steps

1. **Review** the changes in this pull request.
2. **Push** any additional edits to this branch (`release/v3.0.0-rc.5`).
3. **Merge** this pull request to complete the release.

Merging will automatically build the plugin ZIP and create a [GitHub
release](https://github.com/WordPress/sqlite-database-integration/releases).

> [!NOTE]
> This is a **pre-release**. It will not be deployed to
[WordPress.org](https://wordpress.org/plugins/sqlite-database-integration/).