Stuck at commit?

Sorry I can’t figure out a reproducible example for this. But in a real world project, whenever 100 keys were added, reopen the Sqlitedict will stuck at the commit below.

        logger.info("opening Sqlite table %r in %s" % (tablename, filename))
        MAKE_TABLE = 'CREATE TABLE IF NOT EXISTS "%s" (key TEXT PRIMARY KEY, value BLOB)' % self.tablename
        logger.info(MAKE_TABLE)
        self.conn = self._new_conn()
        logger.info("execute")
        self.conn.execute(MAKE_TABLE)
        logger.info("commit")
        self.conn.commit()

I tried to reproduce this in an isolated example, but the problem doesn’t happen in this example. But I attached it below anyway. My values contains nested dictionaries and about 30 fields, about 180K on disk. I switched to shelve because I have no idea what could be the cause. JFYI.

import sqlitedict


def ss():
    return sqlitedict.SqliteDict("cache.sqlite", autocommit=True)

for i in range(3000000):
    key = f"key-{i}"
    print(key)
    with ss() as sd:
        sd[key] = dict(foo=1, nested=dict(bar=1))

[chengguangnan]

Ha, I know what’s going on. The problematic call was inside a __del__ function upon program exit. I guess the some sqlitedict internal stuff has been disposed at that time?

I was trying to save unsaved content in the __del__ function. Maybe not a good place to do that.

[menshikh-iv]

@chengguangnan more safe way for “free” some resources is context manager, like

with MyResource() as resource:
    # make what's needed

also, good post about it - https://eli.thegreenplace.net/2009/06/12/safely-using-destructors-in-python/