尝试将数据库附加到当前打开的数据库，但我收到一条错误，说SQL不允许ATTACH

I'm trying to attach a database(db2.sqlite) to a currently open database(db1.sqlite) and copy the contents of one of the tables in db2 into one of the tables in db1. The logical way to do this I thought was to use the attach command and then select all from db2 and insert into db1:-I'm trying to attach a database(db2.sqlite) to