使用python 2.7将csv文件加载到mysql中

Question

I am trying to insert csv file into mysql using python. I am just new programmer for mysql, so I am not sure what is the problem. Here is my code:

file = csv.reader(file('20184329:2143.csv'))
for row in file:
    sql_insert_table = ("""INSERT INTO STAGING(ADRESSE_1600 ,
                        ADRESSE_1601, ADRESSE_1602, ADRESSE_1603)
                        VALUES ('%s', '%d', '%d', '%s')""", row)
    cursor.execute(sql_insert_table)

And here is the problem:

Traceback (most recent call last):
  File "python_loaddata.py", line 22, in <module>
    cursor.execute(sql_insert_table)
  File "/usr/lib/python2.7/site-packages/MySQLdb/cursors.py", line 161, in execute
    self.errorhandler(self, TypeError, m)
  File "/usr/lib/python2.7/site-packages/MySQLdb/connections.py", line 35, in defaulterrorhandler
    raise errorclass, errorvalue
TypeError: must be string or read-only buffer, not tuple

Answer 1

According to the MySQL execute method docs , the first argument should be the SQL string.

You are passing a tuple, with the query and the tuple.

So just change to:

file = csv.reader(file('20184329:2143.csv'))
sql_insert_table = """INSERT INTO STAGING(ADRESSE_1600 ,
                      ADRESSE_1601, ADRESSE_1602, ADRESSE_1603)
                      VALUES ('%s', '%d', '%d', '%s')"""
for row in file:
    cursor.execute(sql_insert_table, params=row)

Note that you can just pass the row as is because the csv.reader returns a list of strings.

Answer 2

cursor.execute() expects a sql statement (as string) and an optional sequence of values, so it should have been either:

# this will build a (statement, (values,....)) tuple
args = "INSERT INTO STAGING(ADRESSE_1600 ,
                    ADRESSE_1601, ADRESSE_1602, ADRESSE_1603)
                    VALUES ('%s', '%d', '%d', '%s')", (row[i],i)

# so you need positional arguments unpacking:
cursor.execute(*args)

or you can use:

sql = "INSERT INTO STAGING(ADRESSE_1600 ,
                    ADRESSE_1601, ADRESSE_1602, ADRESSE_1603)
                    VALUES ('%s', '%d', '%d', '%s')"
cursor.execute(sql, (row[i],i))

Answer 3

You've got two problems here, and are close to a common security hole.

It looks like you're trying to use % -style substitution to create your insert statement. I say that because you've quoted your parameters in the SQL string. That's a really, really bad idea : if somebody enters their address as, say, ');DROP TABLE STAGING;-- then you'll end up executing their SQL. Instead, use SQL-style placeholders. Those show up as if they were just literals, like VALUES (%s) , not VALUES ('%s') .

Even though the parameters look like they're just going to be %-substituted, as if you used Python's % operator, they're not. The actual values will be used in their stead. So, don't quote them.

The reason for your error, though, is that the statement and the parameters to be used are two separate arguments to cursor.execute . You're currently passing them in as a single argument that's a 2-long tuple.

Here's a fixed version:

sql_insert_table = """INSERT INTO STAGING(ADRESSE_1600 ,
                   ADRESSE_1601, ADRESSE_1602, ADRESSE_1603)
                   VALUES (%s, %s, %s, %s)"""
file = csv.reader(file('20184329:2143.csv'))
for row in file:
    cursor.execute(sql_insert_table, row)