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I've had the same problem with Python, not just Go. If it's a driver problem, it's a very widespread one, which would point out to SQLite driver API being in ne

I've had the same problem with Python, not just Go. If it's a driver problem, it's a very widespread one, which would point out to SQLite driver API being in need of some love if so many folks who write SQLite drivers are making the same mistake.

blattimwind 8y ago
The Python driver is buggy-by-default. This has been documented in recent versions [1], and is kinda sane for the undo log, but not so good if you want to use snapshot isolation. I guess many bindings would make the same decision. Basically they delay the emission of BEGIN until the first DML/DDL is executed. If you fix this (which is easy), then WAL works just fine. Note that transactions, as is standard, span from BEGIN/COMMIT to COMMIT/ROLLBACK. See e.g. https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#transaction-isolation-level https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#t... and https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#pysqlite-serializable https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#p... [1] Really it's more like "encoded": https://docs.python.org/3/library/sqlite3.html#controlling-transactions https://docs.python.org/3/library/sqlite3.html#controlling-t... -- you already need to know the issue to understand that this section specifies the root cause.
- rolleiflex 8y ago
  Interesting! The last time I used this with Python was 2014, and this, alongside the botched migration to 3 was the reason I moved on from Python to Go. Glad to hear things have been improving.
manigandham 8y ago
SQLite has billions of global installs and is tested and certified under incredibly stringent conditions for use in applications like aircraft avionics. Unless there is serious evidence to the contrary, it's pretty much guaranteed that it's not the cause of the issue. How many drivers have you actually tested? There are 2 comments from 2016 on that thread saying other drivers do work fine.

blattimwind 8y ago

The Python driver is buggy-by-default. This has been documented in recent versions [1], and is kinda sane for the undo log, but not so good if you want to use snapshot isolation. I guess many bindings would make the same decision. Basically they delay the emission of BEGIN until the first DML/DDL is executed. If you fix this (which is easy), then WAL works just fine. Note that transactions, as is standard, span from BEGIN/COMMIT to COMMIT/ROLLBACK. See e.g. https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#transaction-isolation-level https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#t... and https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#pysqlite-serializable https://docs.sqlalchemy.org/en/latest/dialects/sqlite.html#p... [1] Really it's more like "encoded": https://docs.python.org/3/library/sqlite3.html#controlling-transactions https://docs.python.org/3/library/sqlite3.html#controlling-t... -- you already need to know the issue to understand that this section specifies the root cause.

rolleiflex 8y ago
Interesting! The last time I used this with Python was 2014, and this, alongside the botched migration to 3 was the reason I moved on from Python to Go. Glad to hear things have been improving.

manigandham 8y ago

SQLite has billions of global installs and is tested and certified under incredibly stringent conditions for use in applications like aircraft avionics. Unless there is serious evidence to the contrary, it's pretty much guaranteed that it's not the cause of the issue. How many drivers have you actually tested? There are 2 comments from 2016 on that thread saying other drivers do work fine.