Update SQLite Database Integration to v3.0.0-rc.1

[wojtekn]

Related issues

• Related to https://github.com/WordPress/sqlite-database-integration/releases/tag/v3.0.0-rc.1

How AI was used in this PR

Claude Code identified and applied all changes.

Proposed Changes

• Bump SQLITE_DATABASE_INTEGRATION_VERSION from v2.2.23 to v3.0.0-rc.1
• Remove WP_SQLITE_AST_DRIVER: true from defaultConstants in wordpress-server-child.ts
• Remove php.defineConstant('WP_SQLITE_AST_DRIVER', true) from run-wp-cli-command.ts
• Define DB_NAME: 'wordpress' at runtime in both wordpress-server-child.ts and run-wp-cli-command.ts

The WP_SQLITE_AST_DRIVER constant was a feature flag enabling the new AST-based driver in earlier versions. Starting with v3.0.0, the old driver has been removed and the flag is no longer needed.

SQLite v3.0.0 also removed the fallback for a missing DB_NAME — it now requires a non-empty value at runtime or it bails with "Error establishing a database connection". Studio strips the default MySQL constants (including DB_NAME) from wp-config.php after site creation, which previously worked because v2 had a 'database_name_here' fallback. We fix this by explicitly defining DB_NAME: 'wordpress' as a runtime constant (the same value Playground's ensureWpConfig would set), so sites where DB_NAME was stripped still work correctly.

Testing Instructions

• Create a new local site and verify it starts correctly on first launch (no "Error establishing a database connection")
• Restart an existing site and verify it still works
• Run a WP-CLI command (e.g. wp option get siteurl) and confirm it works

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wpmobilebot]

📊 Performance Test Results

Comparing 81e21a4 vs trunk

app-size

Metric	trunk	81e21a4	Diff	Change
App Size (Mac)	1482.75 MB	1492.66 MB	+9.91 MB	🔴 0.7%

site-editor

Metric	trunk	81e21a4	Diff	Change
load	1924 ms	1847 ms	77 ms	🟢 -4.0%

site-startup

Metric	trunk	81e21a4	Diff	Change
siteCreation	8100 ms	10139 ms	+2039 ms	🔴 25.2%
siteStartup	4948 ms	5932 ms	+984 ms	🔴 19.9%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff)

[sejas]

Changes look good. Existing sites were updated. New version doesn't have a version.php but the new version can be found in readme.txt
I tried starting existing sites, creating new ones, creating preview sites and authenticating and pushing a new site. Everything worked smoothly.

[wojtekn]

Thanks @sejas !

The version.php which defines the constant is still there, in wp-includes/database/ and it defines the correct version. When I dump SQLITE_DRIVER_VERSION constant in wp-config.php, I see:

string(10) "3.0.0-rc.1"

But it uncovers another issue - when Studio copies the SQLite plugin to the site directory, it doesn't remove the existing files, so after each update, the directory contains not only new files, but old ones, too.

[wojtekn]

@sejas I fixed the mentioned issue: 81e21a4

[sejas]

Thanks for fixing it! 🙌