Python MySQLdb更新值慢

Question

我试图用csv文件中的值更新数据库，下面是我的代码：

import MySQLdb as mdb
import sys
import csv

con = None
command = ''
new_name_list = []
old_name_list = []
duplicates = []
update_list = []
file = 'csv_file.csv'
listReader = csv.reader(open(file, 'r'))
for row in listReader:
    new_name_list.append(row)

try:

    con = mdb.connect('localhost', 'root', 'mypassword', 'mydb')
    con.autocommit(True)

    cur = con.cursor()
    cur.execute("SELECT fil_name FROM file WHERE fil_name like 'boy%' and fil_job_id=1")    

    numrows = int(cur.rowcount)

    for i in range(numrows):
        file_name = cur.fetchone()
    old_name_list.append(file_name[0])

    d = dict(new_name_list)

    for n in old_name_list:
        try:
            print n + " has been updated to " +  d[n]
            command = "UPDATE file SET fil_name='" + d[n] + "' WHERE fil_name='" + n + "'"
            cur.execute(command)
        except KeyError:
            duplicates.append(n)

except mdb.Error, e:

    print "Error %d: %s" % (e.args[0],e.args[1])
    sys.exit(1)

finally:    

    if con:    
        con.close()

每次打印大约需要2-3秒，这使我认为更新执行是缓慢的。我有很多值要更新，这不应该是它应该执行的速度(考虑到我能够快速打印出d[n]的所有值)

还有加速更新的地方吗？

编辑：数据库正在使用InnoDB引擎

Answer 1

您可以尝试使用executemany

data = [(n, d[n]) for n in old_name_list]
cur.executemany("UPDATE file SET fil_name='%s'  WHERE fil_name='%s'", data)

此外，您可能需要考虑索引fil_name (假设fil_name是读的-主要是)