蜗牛之路

import sqlite3
con=sqlite3.connect('posted.db')
print('Opened database successfully')
cursor = con.cursor()
# cur.execute('''CREATE TABLE IF NOT EXISTS herbel
        #(ID INT PRIMARY KEY    NOT NULL,
        #ch_name        TEXT    NOT NULL,
        # age            INT     NOT NULL,
        # address        CHAR(50),
        # salary         REAL
        # );''')
cursor.execute('CREATE TABLE IF NOT EXISTS posturl(id INTEGER PRIMARY KEY,url TEXT,url_md5 TEXT)') #插入有逗号的内容，用两个单引号替换一个单引号
print('Table created successfully')
con.commit()
#connection.close()

#查看数据库中是否已经存在url
def get_data_from_db(url_md5):
    cursor.execute('''select * from posturl where url_md5='%s' ''' % (url_md5))
    results = cursor.fetchall()
    if len(results) > 0:
        return results
    else:
        return None

#将采集完成的url写入本地数据posted数据库中，防止重复采集。
def posted_url_to_db(url,url_md5):
    # url_md5 = get_md5(url)
    sql ="INSERT or IGNORE INTO posturl(url,url_md5) VALUES ('%s','%s')"%(url,url_md5) #最前面的引号要变成双引号,ignore表示忽略重复数据，不过先要设定索引
    try:
        cursor.execute(sql)
        tag_id = cursor.lastrowid
        con.commit()
        print('url为{}写入数据库成功！md5为{}'.format(url,url_md5))
        print("*"*150)
    except:
        con.rollback()
        traceback.print_exc()
        print('url为{}写入数据库失败！'.format(url))
        tag_id = 0
        print("*"*150)

cursor.close()
con.close()