使用Python插入MySQL数据库后，如何获得“ id”？

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问题：使用Python插入MySQL数据库后，如何获得“ id”？

我执行INSERT INTO语句

cursor.execute("INSERT INTO mytable(height) VALUES(%s)",(height))

我想获取主键。

我的表有2列：

id      primary, auto increment
height  this is the other column.

我刚插入这个后，如何获得“ id”？

I execute an INSERT INTO statement

cursor.execute("INSERT INTO mytable(height) VALUES(%s)",(height))

and I want to get the primary key.

My table has 2 columns:

id      primary, auto increment
height  this is the other column.

How do I get the “id”, after I just inserted this?

回答 0

使用cursor.lastrowid得到插入光标对象的最后一行ID，或者connection.insert_id()从该连接上最后插入获取的ID。

Use cursor.lastrowid to get the last row ID inserted on the cursor object, or connection.insert_id() to get the ID from the last insert on that connection.

回答 1

另外，cursor.lastrowid（MySQLdb支持的dbapi / PEP249扩展名）：

>>> import MySQLdb
>>> connection = MySQLdb.connect(user='root')
>>> cursor = connection.cursor()
>>> cursor.execute('INSERT INTO sometable VALUES (...)')
1L
>>> connection.insert_id()
3L
>>> cursor.lastrowid
3L
>>> cursor.execute('SELECT last_insert_id()')
1L
>>> cursor.fetchone()
(3L,)
>>> cursor.execute('select @@identity')
1L
>>> cursor.fetchone()
(3L,)

cursor.lastrowidconnection.insert_id()比另一次MySQL往返便宜，而且便宜很多。

Also, cursor.lastrowid (a dbapi/PEP249 extension supported by MySQLdb):

>>> import MySQLdb
>>> connection = MySQLdb.connect(user='root')
>>> cursor = connection.cursor()
>>> cursor.execute('INSERT INTO sometable VALUES (...)')
1L
>>> connection.insert_id()
3L
>>> cursor.lastrowid
3L
>>> cursor.execute('SELECT last_insert_id()')
1L
>>> cursor.fetchone()
(3L,)
>>> cursor.execute('select @@identity')
1L
>>> cursor.fetchone()
(3L,)

cursor.lastrowid is somewhat cheaper than connection.insert_id() and much cheaper than another round trip to MySQL.

回答 2

Python DBAPI规范还为光标对象定义了“ lastrowid”属性，因此…

id = cursor.lastrowid

…也应该起作用，并且显然基于每个连接。

Python DBAPI spec also define ‘lastrowid’ attribute for cursor object, so…

id = cursor.lastrowid

…should work too, and it’s per-connection based obviously.

回答 3

SELECT @@IDENTITY AS 'Identity';

要么

SELECT last_insert_id();

SELECT @@IDENTITY AS 'Identity';

SELECT last_insert_id();

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