我不明白为什么它不起作用。我已经创建了几个数据库和表,显然没有问题。但是我坚持使用从 django 数据模型创建的这个表。为了阐明我做了什么,从 mysql 控制台创建了新的数据库和表,并尝试从 python 插入并工作。但是,这个对我来说很奇怪。
class Experiment(models.Model):
user = models.CharField(max_length=25)
filetype = models.CharField(max_length=10)
createddate= models.DateField()
uploaddate = models.DateField()
time = models.CharField(max_length=20)
size = models.CharField(max_length=20)
located= models.CharField(max_length=50)
这是mysql控制台中的 View
mysql> describe pmass_experiment;
+-------------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+-------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| user | varchar(25) | NO | | NULL | |
| filetype | varchar(10) | NO | | NULL | |
| createddate | date | NO | | NULL | |
| uploaddate | date | NO | | NULL | |
| time | varchar(20) | NO | | NULL | |
| size | varchar(20) | NO | | NULL | |
| located | varchar(50) | NO | | NULL | |
+-------------+-------------+------+-----+---------+----------------+
8 rows in set (0.01 sec)
上面的pmass_experiment表是由django ORM在python manage.py syncdb之后创建的
现在我尝试通过python MySQLdb将数据插入到pmass_experiment
import MySQLdb
import datetime,time
import sys
conn = MySQLdb.connect(
host="localhost",
user="root",
passwd="root",
db="experiment")
cursor = conn.cursor()
user='tchand'
ftype='mzml'
size='10MB'
located='c:\'
date= datetime.date.today()
time = str(datetime.datetime.now())[10:19]
#Insert into database
sql = """INSERT INTO pmass_experiment (user,filetype,createddate,uploaddate,time,size,located)
VALUES (user, ftype, date, date, time, size, located)"""
try:
# Execute the SQL command
cursor.execute(sql)
# Commit your changes in the database
conn.commit()
except:
# Rollback in case there is any error
conn.rollback()
# disconnect from server
conn.close()
但是,不幸的是没有插入任何东西。我猜这可能是由于表中的 primary_key (id) 没有自动递增。
mysql> select * from pmass_experiment;
Empty set (0.00 sec)
你能简单地指出我的错误吗?
谢谢
最佳答案
sql = """INSERT INTO pmass_experiment (user,filetype,createddate,uploaddate,time,size,located)
VALUES (user, ftype, date, date, time, size, located)"""
参数化您的 sql 并将值作为第二个参数传递给 cursor.execute
:
sql = """INSERT INTO pmass_experiment (user,filetype,createddate,uploaddate,time,size,located)
VALUES (%s, %s, %s, %s, %s, %s, %s)"""
try:
# Execute the SQL command
cursor.execute(sql,(user, ftype, date, date, time, size, located))
# Commit your changes in the database
conn.commit()
except Exception as err:
# logger.error(err)
# Rollback in case there is any error
conn.rollback()
始终参数化您的 sql 是一个好习惯,因为这将有助于防止 sql injection .
原始sql
INSERT INTO pmass_experiment (user,filetype,createddate,uploaddate,time,size,located)
VALUES (user, ftype, date, date, time, size, located)
似乎是有效的。 mysql
shell 中的实验表明它插入了一行 NULL 值:
mysql> insert into foo (first,last,value) values (first,last,value);
Query OK, 1 row affected (0.00 sec)
mysql> select * from foo order by id desc;
+-----+-------+------+-------+
| id | first | last | value |
+-----+-------+------+-------+
| 802 | NULL | NULL | NULL |
+-----+-------+------+-------+
1 row in set (0.00 sec)
所以我不确定为什么您看不到任何提交到数据库表的行。
然而,原始的 sql 可能没有按照您的意图进行。
关于python - MySQL Python Insert 奇怪?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/7860326/