SQLite does not support modifying the primary key after the table is built, or deleting the column, if you want to modify it, refer to the following procedure

SQLite have limited ALTER TABLE support so can use the add a column to the end of a TABLE or to change the name of a T Able. If you want to make more complex changes in the structure of a table, you'll have the table with to recreate. You can save existing data to a temporary table, drop the old table, create the new table, and then copy the data. The temporary table.

For example, suppose you has a table named "T1" with columns names "A", "B", and "C" and so you want to delete column " C "from this table. The following steps illustrate how this could is done:

BEGIN TRANSACTION; CREATE temporary table T1_backup (A, b), INSERT into T1_backup SELECT A, from t1;drop table T1; CREATE table T1 (A, b); INSERT into T1 SELECT A, from T1_backup;drop TABLE t1_backup; COMMIT;

Http://sqlite.org/faq.html#q11

Http://stackoverflow.com/questions/946011/sqlite-add-primary-key

SQLite does not support modifying the primary key after the table is built, or deleting the column, if you want to modify it, refer to the following procedure