import argparse import os import sqlite3 import sys MIGRATE_QUERY = ''' INSERT INTO {tablename} SELECT othertable.* FROM other.{tablename} othertable LEFT JOIN {tablename} mytable ON mytable.id == othertable.id WHERE mytable.id IS NULL AND {where_clause}; ''' def _migrate_helper(sql, tablename, where_clause='1==1'): query = MIGRATE_QUERY.format(tablename=tablename, where_clause=where_clause) print(query) oldcount = sql.execute('SELECT count(*) FROM %s' % tablename).fetchone()[0] sql.execute(query) sql.commit() newcount = sql.execute('SELECT count(*) FROM %s' % tablename).fetchone()[0] print('Gained %d items.' % (newcount - oldcount)) def merge_db(from_db_path, to_db_path, channel): to_db = sqlite3.connect(to_db_path) from_db = sqlite3.connect(from_db_path) to_db.execute('ATTACH DATABASE "%s" AS other' % from_db_path) if channel == '*': _migrate_helper(to_db, 'channels') _migrate_helper(to_db, 'videos') else: _migrate_helper(to_db, 'channels', where_clause=f'othertable.id == "{channel}"') _migrate_helper(to_db, 'videos', where_clause=f'othertable.author_id == "{channel}"') def merge_db_argparse(args): return merge_db(args.from_db_path, args.to_db_path, args.channel) def main(argv): parser = argparse.ArgumentParser(description=__doc__) parser.add_argument('--from_db_path', dest='from_db_path', required=True) parser.add_argument('--to_db_path', dest='to_db_path', required=True) parser.add_argument('--channel', dest='channel', required=True) parser.set_defaults(func=merge_db_argparse) args = parser.parse_args(argv) return args.func(args) if __name__ == '__main__': raise SystemExit(main(sys.argv[1:]))