How to replicate data from table of one database to table in another database atomically in SQLite in iOS Objective-C

Question

I have tried to prepare sqlite3_prepare_v2 and sqlite3_step the following two statements:

@"delete from students;

@"insert into students select * from buffer.students;"

with 'buffer' being the database being attached as the source.

However, this does not guarantee both two statements were executed in bundle.