The docs are correct, you just misinterpreted the behavior of SQLite and Peewee in this case. In order to save CPU and RAM with SQLite, Peewee uses the native rowid field rather than specifically requiring globally unique auto-incrementing ids with SQLite. We can auto increment a field value by using AUTOINCREMENT keyword when creating a table with specific column name to auto incrementing it.
If you need to depend on your rowid, make it an INTEGER PRIMARY KEY, then it is guaranteed not to change”. Peewee does create an auto-incrementing primary key field named 'id' automatically. The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed. Rowids are changed!!!! So please take extra care when you define a table and need to reference records using rowids.įrom the official documentation: “Rowids can change at any time and without notice. Now, perform a VACUUM on the database and run again the query: Now perform again: SELECT rowid,* FROM test Be aware that according to the SQLite documentation, they discourage the use of autoincrement. ', but you can fetch this id by using 'select rowid. This field is usually left out when you use 'select. INSERT INTO test (name) VALUES (‘house’) SQLite creates a unique row id (rowid) automatically. INSERT INTO test (name) VALUES (‘gregory’) INSERT INTO test (name) VALUES (‘giuly’) SQLite AUTOINCREMENT is a keyword used for auto incrementing a value of a field in the table. INSERT INTO test (name) VALUES (‘marco’) You can test this example with SQLiteManager. As always a simple example worths more than 1000 words. The reason for there being no autoincrement for the SQLite would be good note in documentation so we know what going on It is very confusing when the documentation say 'Because we have not specified a primary key, peewee will automatically add an auto-incrementing integer primary key field named id. If you don’t want to read the whole post then just do this: Every time you create a table with sqlite make sure to have an INTEGER PRIMARY KEY AUTOINCREMENT column (the rowid column will be an alias to this one).Ī lot of people don’t realize that a rowid can change. Introduction to SQLite ROWIDtable Whenever you create a tablewithout specifying the WITHOUT ROWIDoption, you get an implicit auto-increment column called rowid. I posted this article in my old blog on Sunday, Janubut I think it’s so important that I decided to re-post it again here. Home SQLite Tutorial SQLite AUTOINCREMENT SQLite AUTOINCREMENT Summary: in this tutorial, you will learn about SQLite AUTOINCREMENTcolumn attribute and when to use it in your table.
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