SQLITE_LOCKED

The SQLITE_LOCKED result code indicates that a write operation could not continue because of a conflict within the same database connection or a conflict with a different database connection that uses a shared cache. For example, a DROP TABLE statement cannot be run while another thread is reading from that table on the same database connection because dropping the table would delete the table out from under the concurrent reader. The SQLITE_LOCKED result code differs from SQLITE_BUSY in that SQLITE_LOCKED indicates a conflict on the same database connection (or on a connection with a shared cache) whereas SQLITE_BUSY indicates a conflict with a different database connection, probably in a different process.