python操作mysql实例

#coding=utf-8
import MySQLdb

# 打开数据库连接
db = MySQLdb.connect(host='localhost',user='root',passwd='',db ='company')
# 使用cursor()方法获取操作游标
cursor = db.cursor()
# 使用execute方法执行SQL语句
cursor.execute("SELECT VERSION()")
# 使用 fetchone() 方法获取一条数据库
data = cursor.fetchone()
print "Database version : %s" %data

# 这个方法用来打印整张表的信息
def view_table(tablename):
    cursor.execute("SELECT * FROM %s" % (tablename))
    results = cursor.fetchall()
    for row in results:
        i = 0
        while i < len(row):
            print row[i],
            i+=1
        print '
'

# 创建数据表SQL语句
cursor.execute("DROP TABLE IF EXISTS employee")
table = """CREATE TABLE employee (
first_name char(20) NOT NULL,
last_name char(20),
age int,
sex char(1),
income float
)"""
cursor.execute(table)
cursor.execute("DESCRIBE employee")
#print cursor.fetchall()
#返回的是一个元组

for tup in cursor.fetchall():
    print tup

sql_1 = '''INSERT INTO employee (FIRST_NAME, LAST_NAME, AGE, SEX, INCOME)
                        VALUES ('Micheal', 'Scofield', 21, 'M', 2000)'''
sql_2 = '''INSERT INTO employee (FIRST_NAME, LAST_NAME, AGE, SEX, INCOME)
                        VALUES ('John', 'Abruzzi', 31, 'F', 3500)'''
sql_3 = '''INSERT INTO employee (FIRST_NAME, LAST_NAME, AGE, SEX, INCOME)
                        VALUES ('Alex', 'Mahone', 35, 'M', 2800)'''
sql_4 = '''INSERT INTO employee (FIRST_NAME, LAST_NAME, AGE, SEX, INCOME)
                        VALUES ('Paul', 'Keleman', 28, 'M', 3700)'''
try:
    cursor.execute(sql_1)
    cursor.execute(sql_2)
    cursor.execute(sql_3)
    cursor.execute(sql_4)
    # 提交到数据库执行
    db.commit()
except:
    #如果上面的语句执行出错就回滚
    db.rollback()

view_table('employee')
#cursor.execute("SELECT * FROM employee")
#results = cursor.fetchall()
#for row in results:
#    fname = row[0]
#    lname = row[1]
#    age = row[2]
#    sex = row[3]
#    income = row[4]
#    print "fname=%s,lname=%s,age=%d,sex=%s,income=%d" % 
#          (fname,lname,age,sex,income)
#    print row[0],row[1],row[2],row[3],row[4]

sql_5 = """UPDATE employee SET age = age+1 WHERE sex = '%c'""" % ('M')
cursor.execute(sql_5)
db.commit()

view_table('employee')
# 关闭数据库连接
db.close()