![]() ![]() This is due to the way auto-incrementing works when omitting the AUTOINCREMENT keyword vs using that keyword. One benefit of omitting the AUTOINCREMENT keyword is that it reduces CPU, memory, disk space, and disk I/O overhead.Īn important downside however, is that you can’t guarantee that all rows will be incremented in ascending order. You can access the ROWID value by using any of four names the column name, ROWID, _ROWID_, or OID. In other words, if you insert NULL into that column, it will be converted to the current ROWID.Īctually, the way it works is that the column becomes an alias for the ROWID. When you do this, any NULL values are converted into the the current ROWID. Therefore, you don’t actually need to use the AUTOINCREMENT keyword to have a column that uses an automatically incrementing value for each row. When you declare a column as INTEGER PRIMARY KEY, it will automatically increment. However, there are some subtle differences between how each method works. One downside of this method is that it uses extra CPU, memory, disk space, and disk I/O overhead.īoth methods cause the column to use an incrementing value each time a new row is inserted with NULL in that column. You can create it explicitly with the AUTOINCREMENT keyword.You can create it implicitly when you define the column as INTEGER PRIMARY KEY.There are a couple of ways you can create an AUTOINCREMENT column: In SQLite, an AUTOINCREMENT column is one that uses an automatically incremented value for each row that’s inserted into the table.
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