python从postgis获取数据写入本地（Postgre入门四）

1、准备数据库数据

2、python读取写入本地

from PIL import Image
import psycopg2 as ps
import os
from io import BytesIO 

def getconn():
     return ps.connect(database=database,user=user,password=password,host=host,port=port)
# 查询表数据
def query(sql):
     conn= getconn()
     cursor = conn.cursor()
     cursor.execute(sql)
     # 返回所有数据
     class_list = cursor.fetchall()
     cursor.close()
     conn.close()
     return class_list
if __name__ == "__main__":
     tablename="img_test"
     sql = "select * from cataract;"
     # 1、从postgis中获取数据
     datas=query(sql)
     # 2、数据写入本地
     for data in datas:
          name = data[0]
          if os.path.exists(os.path.dirname(name))!=True:
               os.makedirs(os.path.dirname(name))
          content = data[1]
          img = Image.open(BytesIO(content))
          img.save(name)

3、结果