Should PostgreSQL connections be pooled in a Python web app, or create a new connection per request?

Question

I\'m building a web app in Python (using Flask). I do not intend to use SQLAlchemy or similar ORM system, rather I\'m going to use Psycopg2 directly.

Should I open a new

Answer 1

Yeah connection pooling will help but yes you have to find out the right numbers for live connection or pool size based on which load will be on database.

    from psycopg2.pool import SimpleConnectionPool
    from contextlib import contextmanager

    dbConnection = "dbname='dbname' user='postgres' host='localhost' password='postgres'"

    # pool define with 10 live connections
    connectionpool = SimpleConnectionPool(1,10,dsn=dbConnection)

    @contextmanager
    def getcursor():
        con = connectionpool.getconn()
        try:
            yield con.cursor()
        finally:
            connectionpool.putconn(con)

    def main_work():
        try:
            # with here will take care of put connection when its done
            with getcursor() as cur:
                cur.execute("select * from \"TableName\"")
                result_set = cur.fetchall()

        except Exception as e:
            print "error in executing with exception: ", e