Python之csv文件从MySQL数据库导入导出

Python从MySQL数据库中导出csv文件处理

csv文件导入MySQL数据库

import pymysql
import csv
import codecs


def get_conn():
    conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='root', db='test_csv', charset='utf8')
    return conn


def insert(cur, sql, args):
    cur.execute(sql, args)


def read_csv_to_mysql(filename):
    with codecs.open(filename=filename, mode='r', encoding='utf-8') as f:
        reader = csv.reader(f)
        head = next(reader)
        conn = get_conn()
        cur = conn.cursor()
        sql = 'insert into tb_csv values(%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)'
        for item in reader:
            if item[1] is None or item[1] == '':  # item[1]做为惟一键，不能为null
                continue
            args = tuple(item)
            print(args)
            insert(cur, sql=sql, args=args)

        conn.commit()
        cur.close()
        conn.close()


if __name__ == '__main__':
    read_csv_to_mysql('1.csv')

注：

• 1.csv文件的表头如：

序号,合同编号,义务人,档案柜号,柜内编号,权利人,放款金额,放款日期,他项权利证编号,抵押物地址,结清出库日期,备注,地区

• mysql的建立tb_csv表语句

CREATE TABLE tb_csv( xuhao VARCHAR(20), htcode VARCHAR(20), yiwuren VARCHAR(20), dagh VARCHAR(20), gncode VARCHAR(20), quanliren VARCHAR(20), fkmoney VARCHAR(20), fkdata VARCHAR(20), qitacode VARCHAR(20), diyaaddr VARCHAR(100), jqdata VARCHAR(30), beizhu VARCHAR(30), zone VARCHAR(30), PRIMARY KEY(htcode) )CHARSET=utf8;

这里为了省事，表中的字段都指明varchar类型

---

MySQL数据库写入csv文件

import pymysql
import csv
import codecs


def get_conn():
    conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='root', db='test_csv', charset='utf8')
    return conn

def query_all(cur, sql, args):
    cur.execute(sql, args)
    return cur.fetchall()


def read_mysql_to_csv(filename):
    with codecs.open(filename=filename, mode='w', encoding='utf-8') as f:
        write = csv.writer(f, dialect='excel')
        conn = get_conn()
        cur = conn.cursor()
        sql = 'select * from tb_csv'
        results = query_all(cur=cur, sql=sql, args=None)
        for result in results:
            print(result)
            write.writerow(result)



if __name__ == '__main__':
    read_mysql_to_csv('2.csv')