psycopg2: insert multiple rows with one query
I need to insert multiple rows with one query (number of rows is not constant), so I need to execute query like this one:
INSERT INTO t (a, b) VALUES (1, 2), (3, 4), (5, 6);
The only way I know is
args = [(1,2), (3,4), (5,6)]
args_str = ','.join(cursor.mogrify("%s", (x, )) for x in args)
cursor.execute("INSERT INTO t (a, b) VALUES "+args_str)
but I want some simpler way.
Answer
I built a program that inserts multiple lines to a server that was located in another city.
I found out that using this method was about 10 times faster than executemany. In my case tup is a tuple containing about 2000 rows. It took about 10 seconds when using this method:
args_str = ','.join(cur.mogrify("(%s,%s,%s,%s,%s,%s,%s,%s,%s)", x) for x in tup)
cur.execute("INSERT INTO table VALUES " + args_str)
and 2 minutes when using this method:
cur.executemany("INSERT INTO table VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)", tup)