MySQLdb.cursor.execute无法运行多个查询

Question

我们正在尝试将包含多个插入语句的SQL文件作为一个查询运行，但是rollback当任何一个语句包含错误时，它似乎都会失败。

MySQLd配置：

sql_mode = STRICT_ALL_TABLES
default-storage-engine = innodb

Python代码：

from contextlib import closing
import MySQLdb
database_connection = MySQLdb.connect(host="127.0.0.1", user="root")
with closing(database_connection.cursor()) as cursor:
    database_connection.begin()
    cursor.execute('DROP DATABASE IF EXISTS db_name')
    cursor.execute('CREATE DATABASE db_name')
    cursor.execute('USE db_name')
    cursor.execute('CREATE TABLE table_name(first_field INTEGER)')
with closing(database_connection.cursor()) as cursor:
    try:
        database_connection.begin()
        cursor.execute('USE db_name')
        cursor.execute('INSERT INTO table_name VALUES (1)')
        cursor.execute('INSERT INTO table_name VALUES ("non-integer value")')
        database_connection.commit()
    except Exception as error:
        print("Exception thrown: {0}".format(error))
        database_connection.rollback()
        print("Rolled back")
with closing(database_connection.cursor()) as cursor:
    try:
        database_connection.begin()
        cursor.execute('USE db_name')
        cursor.execute('INSERT INTO table_name VALUES (1); INSERT INTO table_name VALUES ("non-integer value")')
        database_connection.commit()
    except:
        print("Exception thrown: {0}".format(error))
        database_connection.rollback()
        print("Rolled back")

预期结果：打印两次“抛出异常”和“回滚”。

使用MySQL-python 1.2.4的实际结果：

Exception thrown: (1366, "Incorrect integer value: 'non-integer value' for column 'first_field' at row 1")
Rolled back
Exception thrown: (1366, "Incorrect integer value: 'non-integer value' for column 'first_field' at row 1")
Traceback (most recent call last):
  File "test.py", line 30, in <module>
    print("Rolled back")
  File ".../python-2.7/lib/python2.7/contextlib.py", line 154, in __exit__
    self.thing.close()
  File ".../virtualenv-python-2.7/lib/python2.7/site-packages/MySQLdb/cursors.py", line 100, in close
    while self.nextset(): pass
  File ".../virtualenv-python-2.7/lib/python2.7/site-packages/MySQLdb/cursors.py", line 132, in nextset
    nr = db.next_result()
_mysql_exceptions.OperationalError: (1366, "Incorrect integer value: 'non-integer value' for column 'first_field' at row 1")

是什么赋予了？我们是否真的必须解析SQL以拆分语句（需要进行所有转义和引号处理）才能在多个executes中运行它们？

Answer 1

显然，在MySQLdb（aka。MySQL- python）中无法执行此操作，因此我们最终只是communicate将数据写入subprocess.Popen([mysql, ...], stdin=subprocess.PIPE)并检查returncode。