對於訪問數據庫的操作，我想大家也都有一些了解。不過，因為最近在學習Python，以下就用Python來實現它。其中包括創建數據庫和數據表、插入記錄、刪除記錄、修改記錄數據、查詢數據、刪除數據表、刪除數據庫。還有一點就是我們最好使用一個新定義的類來處理這件事。因為這會使在以後的使用過程中更加的方便（只需要導入即可，避免了重復制造輪子）。
1.封裝一個DB類
2.數據庫操作：創建數據庫和數據表
3.數據庫操作：插入記錄
4.數據庫操作：一次插入多條記錄
5.數據庫操作：刪除記錄
6.數據庫操作：修改記錄數據
7.數據庫操作：一次修改多條記錄數據
8.數據庫操作：查詢數據
9.數據庫操作：刪除數據表
10.數據庫操作：刪除數據庫
heroDB.py
#!/usr/bin/env python
import MySQLdb
DATABASE_NAME = 'hero'
class HeroDB:
# init class and create a database
def __init__(self, name, conn, cur):
self.name = name
self.conn = conn
self.cur = cur
try:
cur.execute('create database if not exists ' + name)
conn.select_db(name)
conn.commit()
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# create a table
def createTable(self, name):
try:
ex = self.cur.execute
if ex('show tables') == 0:
ex('create table ' + name + '(id int, name varchar(20), sex int, age int, info varchar(50))')
self.conn.commit()
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# insert single record
def insert(self, name, value):
try:
self.cur.execute('insert into ' + name + ' values(%s,%s,%s,%s,%s)', value)
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# insert more records
def insertMore(self, name, values):
try:
self.cur.executemany('insert into ' + name + ' values(%s,%s,%s,%s,%s)', values)
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# update single record from table
# name: table name
# values: waiting to update data
def updateSingle(self, name, value):
try:
# self.cur.execute('update ' + name + ' set name=' + str(values[1]) + ', sex=' + str(values[2]) + ', age=' + str(values[3]) + ', info=' + str(values[4]) + ' where id=' + str(values[0]) + ';')
self.cur.execute('update ' + name + ' set name=%s, sex=%s, age=%s, info=%s where id=%s;', value)
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# update some record from table
def update(self, name, values):
try:
self.cur.executemany('update ' + name + ' set name=%s, sex=%s, age=%s, info=%s where id=%s;', values)
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# get record count from db table
def getCount(self, name):
try:
count = self.cur.execute('select * from ' + name)
return count
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# select first record from database
def selectFirst(self, name):
try:
self.cur.execute('select * from ' + name + ';')
result = self.cur.fetchone()
return result
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# select last record from database
def selectLast(self, name):
try:
self.cur.execute('SELECT * FROM ' + name + ' ORDER BY id DESC;')
result = self.cur.fetchone()
return result
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# select next n records from database
def selectNRecord(self, name, n):
try:
self.cur.execute('select * from ' + name + ';')
results = self.cur.fetchmany(n)
return results
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# select all records
def selectAll(self, name):
try:
self.cur.execute('select * from ' + name + ';')
self.cur.scroll(0, mode='absolute') # reset cursor location (mode = absolute | relative)
results = self.cur.fetchall()
return results
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# delete a record
def deleteByID(self, name, id):
try:
self.cur.execute('delete from ' + name + ' where id=%s;', id)
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# delete some record
def deleteSome(self, name):
pass
# drop the table
def dropTable(self, name):
try:
self.cur.execute('drop table ' + name + ';')
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
# drop the database
def dropDB(self, name):
try:
self.cur.execute('drop database ' + name + ';')
except MySQLdb.Error, e:
print "Mysql Error %d: %s" % (e.args[0], e.args[1])
def __del__(self):
if self.cur != None:
self.cur.close()
if self.conn != None:
self.conn.close()
testHeroDB.py
#!/usr/bin/env python
import MySQLdb
from heroDB import HeroDB
def main():
conn = MySQLdb.connect(host='localhost', user='root', passwd='260606', db='hero', port=3306, charset='utf8')
cur = conn.cursor()
# ------------------------------------------- create -----------------------------------------------------
hero = HeroDB('hero', conn, cur)
hero.createTable('heros')
# ------------------------------------------- insert -----------------------------------------------------
hero.insert('heros', [3, 'Prophet', 0, 2000, 'The hero who in fairy tale.'])
# ------------------------------------------- select -----------------------------------------------------
print '-' * 60
print 'first record'
result = hero.selectFirst('heros')
print result
print '-' * 60
print 'last record'
result = hero.selectLast('heros')
print result
print '-' * 60
print 'more record'
results = hero.selectNRecord('heros', 3)
for item in results:
print item
print '-' * 60
print 'all record'
results = hero.selectAll('heros')
for item in results:
print item
# ------------------------------------------- update -----------------------------------------------------
hero.updateSingle('heros', ['Zeus', 1, 22000, 'The god.', 2])
values = []
values.append(['SunWukong', 1, 1300, 'The hero who in fairy tale.', 1])
values.append(['Zeus', 1, 50000, 'The king who in The Quartet myth.', 2])
values.append(['Prophet', 1, 20000, 'The hero who in fairy tale.3', 3])
hero.update('heros', values)
# ------------------------------------------- delete -----------------------------------------------------
hero.deleteByID('heros', 1)
hero.dropTable('heros')
hero.dropDB('hero')
if __name__ == '__main__':
main()
注：請不要不假思索地使用他們。如果你想實現某一個功能點，請最好將其他的功能點注釋掉，這樣才符合單元測試的規范。
