> does sqlite create a index table to mapping this column and rowid columm No. The `integer primary key` is the rowid. If you do not declare a rowid (`integer primary key`) for a rowid table, then one exists anyway, it just does not form part of the persistent data of the table -- it is invisible and subject to change at a whim -- but the rowid may be accessed by the magic name `rowid`, `_rowid_`, or `oid` provided that those names have not been declared elsehow in the rowid table definition.