fix(powersync): use read lock for BucketStorage.select()#432
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BucketStorage.select() is documented for read statements only, but called _internalDb.execute(), which acquires a write lock. All callers run SELECTs, so route them through getAll() to take a read lock instead. This avoids serializing read-only queries behind the write lock (e.g. on web with SqliteConnectionPool). Closes powersync-ja#384
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Closes #384
Problem
BucketStorage.select()is documented "Use only for read statements", but it calls_internalDb.execute(), which acquires a write lock. Every caller (getClientId,updateLocalTarget,hasCrud,getCrudBatch, …) runs read-onlySELECTs, so taking a write lock needlessly serializes these reads behind the write lock — notably on web /SqliteConnectionPool, where reads and writes can otherwise run concurrently.@simolus3 confirmed in the issue that this is a bug.
Fix
Route
select()throughgetAll(), which acquires a read lock, matching the method's documented read-only contract. All existing callers are plainSELECTs, so behaviour is unchanged apart from the correct lock type.Notes
## 2.3.1 (unreleased)).