lohaorder.blogg.se - Sqlite database is locked

#SQLITE DATABASE IS LOCKED UPDATE#
#SQLITE DATABASE IS LOCKED CODE#

#SQLITE DATABASE IS LOCKED CODE#

The code is the exact same that I used previously for updating a PIN. Ive set breakpoints and the query itself is fine. The issue Im running into is that when I INSERT something in a table in. If this happens the cache "spills" and the writer will perform the PENDING -> EXCLUSIVE transition long before the transaction is ready to commit. Ive checked to make sure the db connection is closed elsewhere before its opened during this method, its definitely closed before the function is called and opened before any queries. Im using provider in an ASP.NET application (framework 4.0).

PRAGMAs cache_spill and cache_size - in the case of a large write transaction, the changes made to the database may exceed sqlite's configured memory cache.

BEGIN IMMEDIATE can be useful to avoid wasted effort arising from contention here. Youll need to ensure that you close and/or end the.

starting a write transaction) will fail immediately if PENDING is already held, because there is no point waiting in this scenario. The database file will lock when a write action is being performed such as a insert, delete or update. note this does not apply to all lock acquisitions - in particular escalating from SHARED to PENDING (ie.sqlite3_busy_timeout() which controls how long the library should transparently retry when encountering an SQLITE_BUSY error (aka "database is locked").Other mechanisms to consider in this area are: So if you want things to work smoothly, focusing on short transactions is a good rule of thumb. Asking for help, clarification, or responding to other answers. giving up and aborting the write transaction. Thanks for contributing an answer to Stack Overflow Please be sure to answer the question.Provide details and share your research But avoid. The application itself is in control of this delay though, as it chooses how persistent it should be in acquiring the EXCLUSIVE lock vs. Unable to read while database is locked (1) By Alex (palu3492 ) on 16:15:31 link source Hello, Im using SQLite 3.22.0 in Python 3 with sqlalchemy.

#SQLITE DATABASE IS LOCKED UPDATE#

But it must have the EXCLUSIVE lock to safely update the main database file.Ī consequence of the locking protocol is that any long-running transaction performed by an app has the potential to cause read-transactions to fail with "Database is locked", because if a write-transaction comes in during the long-running transaction, everything else using the DB will ultimately have to wait for the long-running transaction to finish (so the write-transaction can commit its changes). This will fail if any read transactions are still active, so often a writer has to repeatedly retry at this point. Read transactions can no longer start once PENDING is acquired. This indicates that a transaction is ready to be committed. RESERVED does not affect read transactions. This indicates intent to write to the database and will fail if a concurrent write transaction is already in progress. The write-path escalates through these phases: the default) there can only be one writer at any time, but concurrent reads are still allowed until the writer is ready to commit its changes.