![]() ![]() Types cannot be detected for generated fields (for example max(data)),Įven when the detect_types parameter is set str will beīy default ( 0), type detection is disabled. Set it to any combination (using |, bitwise or) ofĬolumn names takes precedence over declared types if both flags are set. Using the converters registered with register_converter(). That table will be locked until the transaction is committed.ĭetect_types ( int) – Control whether and how data types notĪre looked up to be converted to Python types, If another connection opens a transaction to modify a table, Timeout ( float) – How many seconds the connection should wait before raisingĪn OperationalError when a table is locked. Pass ":memory:" to open a connection to a database that is ![]() Parametersĭatabase ( path-like object) – The path to the database file to be opened. connect ( database, timeout = 5.0, detect_types = 0, isolation_level = 'DEFERRED', check_same_thread = True, factory = sqlite3.Connection, cached_statements = 128, uri = False ) ¶ How to use the connection context managerĮxplanation for in-depth background on transaction control. How to convert SQLite values to custom Python types How to adapt custom Python types to SQLite values ![]() If you disconnect from in-memory database, the database gets destroyed, so then you don't need to reset those.How to use placeholders to bind values in SQL queries Group 3 are for example schema_version, user_version, maybe some others, you need to look it up. If you don't disconnect, you will need to reset those to defaults manually. These pragmas are always set to defaults when opening new connection to the database. Group 2 are for example cache_size, recursive_triggers, jurnal_mode, foreign_keys, busy_timeout, etc. You should not need to reset pragmas from group 1. The encoding is defined at creation time and cannot be modified later. The page_count cannot be changed by user, but it changes automatically when adding data (obviously). For example page_size can be changed prior to "VACUUM", so the new page size will be set then. Those are definied at database creation moment and usualle cannot be modified later, with some exceptions. Group 1 are for example page_size, page_count, encoding, etc. defined dynamically, per database, mutable.defined dynamically, per connection, mutable.defined initially, immutable, or very limited mutability.Note, that pragmas in SQLite can be divided to 3 groups: ![]() If your threads don't touch pragmas explicitly, then only "schema_version" pragma can be changed silently, but if your threads can change pragmas, well, then you have to go through the list on and write "reset" function which will set each and every pragma value to it's initial value (you need to read default values at the begining). If there are some other limitations and you cannot do it the way above, then you were already pretty close to have a complete solution. While you have exclusive access to the database connection - why not closing and re-opening it? Therefore even you have multiple threads working on that database, there need to be a "stop the world" mutex (or something like that), so the reset can be performed. If you want to have some kind of "reset" function, you must assume that no other threads can interrupt that function - otherwise any method will fail. It flushes any database data and also per-connection settings. If you use in-memory database, the fastest and most reliable way is to close and re-establish sqlite connection. ![]()
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