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#!/usr/bin/python
import time
import MySQLdb;
conn = MySQLdb.connect(host="localhost",port=3306,user="root",passwd="asdf",db="test",unix_socket="/data/mysql_3306/mysql.sock")
cursor = conn.cursor()
cursor.execute("select * from test")
while str!="1":
    str = raw_input()
cursor.execute("update test id=id-1")
while str!="exit":
    str = raw_input()
cursor.close()
conn.close()
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ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
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#!/usr/bin/python
import time
import MySQLdb;
conn = MySQLdb.connect(host="localhost",port=3306,user="root",passwd="asdf",db="test",unix_socket="/data/mysql_3306/mysql.sock")
cursor = conn.cursor()
cursor.execute("select * from test lock in share mode")
while str!="exit":
    str = raw_input()
cursor.close()
conn.close()
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mysql> update test set id=id-1;
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
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#!/usr/bin/python
import time
import MySQLdb;
conn = MySQLdb.connect(host="localhost",port=3306,user="root",passwd="asdf",db="test",unix_socket="/data/mysql_3306/mysql.sock")
cursor = conn.cursor()
cursor.execute("select * from test lock in share mode")
str = ""
while str!="1":
    str = raw_input()
while str!="2":
    str = raw_input()
cursor.execute("update test set id=id-1")
while str!="exit":
    str = raw_input()
cursor.close()
conn.close()
[root@TJSJHL196-139 tmp]# python test_transaction.py 
1
2
Traceback (most recent call la