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• 测试主要对于在数据库数据抓取后，对数据输出类型的处理，对图片的存取

        MYSQL 是支持把图片存入数据库的，也相应的有一个专门的字段 BLOB (Binary Large Object)，即较大的二进制对象字段

• BLOB类型的字段用于存储二进制数据

CREATE TABLE Images(Id INT PRIMARY KEY AUTO_INCREMENT, Data MEDIUMBLOB);

以上两条语句分别创建两个不同大小的BLOB表

测试如下：

#coding:utf-8#获取版本import MySQLdb as mdbimport sysdb= Nonetry:    db = mdb.connect("localhost","root","chejian","TESTDB")    cursor = db.cursor()    cursor.execute("SELECT VERSION()")    data = cursor.fetchone()    print "Database version : %s" %(data)finally:    if db:        db.close()#创建表并插入数据db = mdb.connect("localhost","root","chejian","TESTDB")cursor = db.cursor()try:    cursor.execute("DROP TABLE IF EXISTS Writers")    cursor.execute("CREATE TABLE IF NOT EXISTS \                    Writers(Id INT PRIMARY KEY AUTO_INCREMENT,Name VARCHAR(25))")    cursor.execute("INSERT INTO Writers(Name) VALUES('Jack London')")    cursor.execute("INSERT INTO Writers(Name) VALUES('Honore de Balzac')")    cursor.execute("INSERT INTO Writers(Name) VALUES('Lion Feuchtwanger')")    cursor.execute("INSERT INTO Writers(Name) VALUES('Emile Zola')")    cursor.execute("INSERT INTO Writers(Name) VALUES('Truman Capote')")    #当对数据库数据改变时，提交到数据库执行    db.commit()except:    #若有错误，则回滚    db.rollback()finally:    if db:        db.close()#提取数据 元组db = mdb.connect("localhost","root","chejian","TESTDB")cursor = db.cursor()sql = "SELECT * FROM Writers"try:    cursor.execute(sql)    #获取结果集的条数    num = int(cursor.rowcount)    for i in range(num):        row = cursor.fetchone()        print  row[0],row[1]except:    print "Error: unable to fetcg data"finally:    if db:        db.close()#使用字典来获取数据db = mdb.connect("localhost","root","chejian","TESTDB")cursor = db.cursor(mdb.cursors.DictCursor)try:    cursor.execute(sql)    rows = cursor.fetchall()    for row in rows:        print row["Id"],row["Name"]except:    print "Error2: unable to fetcg data"finally:    if db:        db.close()#获取单个表的字段名和信息的方法db = mdb.connect("localhost","root","chejian","TESTDB")cursor = db.cursor()try:    cursor.execute(sql)    rows = cursor.fetchall()    desc = cursor.description    print 'cur.description :',desc    for row in rows:        print rowexcept:    print "Error3: unable to fetcg data"    sys.exit(1)finally:    if db:        db.close()#查询影响了多少行db = mdb.connect("localhost","root","chejian","TESTDB")cursor = db.cursor()#sql = "UPDATE Writers SET Name = %s WHERE Id = %s" %("Guy de Mau","4")try:    cursor.execute("UPDATE Writers SET Name = %s WHERE Id = %s" ,("Guy de Mau","4"))    #cursor.execute(sql)    db.commit()    num = int(cursor.rowcount)    print numexcept:    db.rollback()    print "Error3: unable to fetcg data"    sys.exit(1)finally:    if db:        db.close()#CREATE TABLE Images(Id INT PRIMARY KEY AUTO_INCREMENT, Data MEDIUMBLOB);import MySQLdb as mdbimport systry:# 用读文件模式打开图片    fin = open("C:\Users\chejian\Pictures\lovewallpaper\9006-106.jpg")# 将文本读入 img 对象中    img = fin.read()# 关闭文件    fin.close()except IOError, e:# 如果出错，打印错误信息    print "Error %d: %s" % (e.args[0], e.args[1])    sys.exit(1)try:# 链接 mysql，获取对象    conn = mdb.connect(host='localhost', user='root', passwd='chejian', db='testdb')# 获取执行 cursor    cursor = conn.cursor()# 直接将数据作为字符串，插入数据库    cursor.execute("INSERT INTO Images SET Data='%s'" %               mdb.escape_string(img))# 提交数据    conn.commit()#释放资源    cursor.close()except mdb.Error, e:# 若出现异常，打印信息    conn.rollback()    print "Error %d: %s" % (e.args[0], e.args[1])    sys.exit(1)finally:    if conn:        conn.close()try:#连接 mysql，获取连接的对象    conn = mdb.connect(host='localhost', user='root', passwd='chejian',db='testdb');    cursor = conn.cursor()#执行查询该图片字段的 SQL    cursor.execute("SELECT Data FROM Images LIMIT 1")#使用二进制写文件的方法，打开一个图片文件，若不存在则自动创建    fout = open('9006-106.jpg','wb')    #直接将数据如文件    fout.write(cursor.fetchone()[0])#关闭写入的文件    fout.close()#释放查询数据的资源    cursor.close()except IOError, e:#捕获 IO 的异常 ，主要是文件写入会发生错误    print "Error %d: %s" % (e.args[0],e.args[1])    sys.exit(1)finally:    if conn:        conn.close()

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