python使用MySQLdb访问mysql数据库的方法

#!/usr/bin/python
import MySQLdb
def doInsert(cursor,db):
 #insert
 # Prepare SQL query to INSERT a record into the database.
 sql = "UPDATE EMPLOYEE SET AGE = AGE+1 WHERE SEX = '%c'" %('M')
 try:
 cursor.execute(sql)
 db.commit()
 except:
 db.rollback()
def do_query(cursor,db):
 sql = "SELECT * FROM EMPLOYEE 
 WHERE INCOME > '%d'" % (1000)
 try:
 # Execute the SQL command
 cursor.execute(sql)
 # Fetch all the rows in a list of lists.
 results = cursor.fetchall()
 print 'resuts',cursor.rowcount
 for row in results:
 fname = row[0]
 lname = row[1]
 age = row[2]
 sex = row[3]
 income = row[4]
 # Now print fetched result
 print "fname=%s,lname=%s,age=%d,sex=%s,income=%d" % 
 (fname, lname, age, sex, income )
 except:
 print "Error: unable to fecth data"
def do_delete(cursor,db):
 sql = 'DELETE FROM EMPLOYEE WHERE AGE > {}'.format(20)
 try:
 cursor.execute(sql)
 db.commit()
 except:
 db.rollback()
def do_insert(cursor,db,firstname,lastname,age,sex,income):
 sql = "INSERT INTO EMPLOYEE(FIRST_NAME, 
 LAST_NAME, AGE, SEX, INCOME) 
 VALUES ('%s', '%s', '%d', '%c', '%d' )" % 
 (firstname,lastname,age,sex,income)
 try:
 cursor.execute(sql)
 db.commit()
 except:
 db.rollback()
# Open database connection
# change this to your mysql account
#connect(server,username,password,db_name)
db = MySQLdb.connect("localhost","hunter","hunter","pydb" )
# prepare a cursor object using cursor() method
cursor = db.cursor()
do_query(cursor,db)
doInsert(cursor,db)
do_query(cursor,db)
do_delete(cursor,db)
do_query(cursor,db)
do_insert(cursor,db,'hunter','xue',22,'M',2000)
do_insert(cursor,db,'mary','yang',22,'f',5555)
do_insert(cursor,db,'zhang','xue',32,'M',5000)
do_insert(cursor,db,'hunter','xue',22,'M',333)
do_query(cursor,db)
# disconnect from server
db.close()