Sqlite order by string of numbers8/1/2023 ![]() Or None to disable opening transactions implicitly.Ĭheck_same_thread ( bool) – If True (default), ProgrammingError will be raised Isolation_level ( str | None) – The isolation_level of the connection,Ĭontrolling whether and how transactions are implicitly opened.Ĭan be "DEFERRED" (default), "EXCLUSIVE" or "IMMEDIATE" 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 Nearly 25 years since REALbasic 1.0, and the documentation still not have goodies (code snippet that resolve computer real day problems).How to use placeholders to bind values in SQL queries (excepted with my i5/2014 MacBook Pro, but it is a 9 years old computer, and running VirtualBox / Windows 10 does not accelerate things )Īlso, the sort is always 1 at the top (who will seach an integer value Backward ?) and there is a “Search in the Display ListBox” feature available. ![]() On a 575 Row Data Base with 13 Columns (First Name, Family Name, 3 SQLDates, City names…) the impact is very low. But because I display it - so I would have to convert it to String in the ListBox if I store it as INTEGER - I think the speed slow down due to CAST is… peanuts. Yes, I stored that integer value as string. We have a winner here yes, I was happy ! (to wrote this feature and see it works well for the meaning Once again, I forgot something.Ĭasier (in this case) is a numeric value (1 thru I do not know, but low value). SELECT * FROM casier_table ORDER BY SUBSTR(' ' || TRIM(casier), -10) - must match the index indexed expression right aligned with 10 places SELECT * FROM casier_table ORDER BY CAST(casier AS Integer) INSERT INTO "casier_table" VALUES ('f99') INSERT INTO "casier_table" VALUES ('j23') INSERT INTO "casier_table" VALUES ('c37') ![]() INSERT INTO "casier_table" VALUES ('bbb') INSERT INTO "casier_table" VALUES ('nnn') INSERT INTO "casier_table" VALUES ('aaa') INSERT INTO "casier_table" VALUES ('72') INSERT INTO "casier_table" VALUES ('789') INSERT INTO "casier_table" VALUES ('36') Example:ĬREATE INDEX idx_casier_order ON casier_table(SUBSTR(' ' || TRIM(casier), -10)) - expression index Also, when involving mixing alpha and numeric data while ordering, things can get tricky, if this is your case, you probably would like a right aligned value approach. Since SQLite 3.9, SQLite (also) allows indexed expressions, if your current engine allows it, you should try it. You ended with an intense overhead of an entire sort of the involved expressions in this query. The sad part of converting on-the-fly a value in SQLite is losing so much speed that it could have if the column was just numeric and indexed. I guess you have some “Casiers” as “B37” or whatever for such choice.
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