python操作pgSQL
https://blog.csdn.net/qq_36810398/article/details/98845521?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522159255210619725247660027%2522%252C%2522scm%2522%253A%252220140713.130102334…%2522%257D&request_id=159255210619725247660027&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2allfirst_rank_v2~rank_v25-1-98845521.pc_search_back_js&utm_term=python%E6%93%8D%E4%BD%9Cpgsql
#连接数据库需要提供相应的数据库名称、用户名、密码、地址、端口等信息
conn=psycopg2.connect(database=db,user=user,password=pw,host=host,port=port)
curs=conn.cursor()
select_sql="select * from table" #从表格table中读取全表内容
curs.execute( select_sql) #执行该sql语句
data = curs.fetchall() #获取数据
curs.close()
conn.close()
conn=psycopg2.connect(database=db,user=user,password=pw,host=host,port=port)
curs=conn.cursor()
update_sql="UPDATE table SET col_C=3 WHERE col_A=1 AND col_B=2"
insert_sql="insert into table (col_A,col_B,col_C) values {0}".format(str((1,2,3)))
curs.execute(update_sql)
#python这个psycopg2包自带这个属性rowcount，表示上一个操作影响的行数
#如果影响的行数为0，则表中没有满足条件的记录，则写入该行
if curs.rowcount==0:
curs.execute(insert_sql)
conn.commit()
curs.close()
conn.close()
https://blog.csdn.net/weixin_43166227/article/details/97268112?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522159255210619195239855443%2522%252C%2522scm%2522%253A%252220140713.130102334.pc%255Fall.%2522%257D&request_id=159255210619195239855443&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2allfirst_rank_v2~rank_v25-8-97268112.pc_search_back_js&utm_term=python%E6%93%8D%E4%BD%9Cpgsql
#!/usr/bin/python
import psycopg2
from datetime import datetime
db_host = "xxxxxx-esb-xx.xxxxx.xx-xxxx.rds.xxxxx.com"
db_port = 5432
db_name = "xxx"
db_user = "xxx"
db_pass = "xxxx"
db_table = "xxxxx"
biller_code = "111111"
biller_short_name = "test_short"
biller_long_name = "test_long"
def make_conn():
conn = None
try:
conn = psycopg2.connect("dbname='%s' user='%s' host='%s' password='%s'" % (db_name, db_user, db_host, db_pass))
print "connected to postgres db successfully"
except:
print "I am unable to connect to the database"
return conn
try:
connection = make_conn()
cursor = connection.cursor()
cursor.execute("SELECT * FROM billers where biller_code = '%s';" % biller_code)
numOfRows = cursor.rowcount
print("%s rows found for the biller code: %s" % (numOfRows, biller_code))
if(numOfRows<=0):
dt = datetime.now()
cursor.execute("insert into billers (biller_code, biller_short_name, biller_long_name, active, min_length, max_length, reg_exp, check_digit_algo, created_at, updated_at) values (%s, %s, %s, true, 0, 100, 'NONE', 'NONE', %s, %s)", (biller_code, biller_short_name, biller_long_name, dt, dt))
connection.commit()
print("inserted %s rows successfully" % cursor.rowcount)
except (Exception, psycopg2.Error) as error :
print ("Error caught", error)
finally:
#closing database connection.
if(connection):
cursor.close()
connection.close()
print("PostgreSQL connection is closed")
可用用的带变量的方法，不用直接写数值
#!/usr/bin/python
# -*- coding: UTF-8 -*-
import string
import psycopg2
import random
from psycopg2 import extras
address_list = {'北京', '上海', '深圳', '广州', '长沙', '成都', '吉林', '邵阳', '九江', '长春', '拉萨'}
conn = psycopg2.connect(database="test", user="test", password="test", host="127.0.0.1", port="5433")
print("Opened database successfully")
cur = conn.cursor()
# values 后面直接%s
sql = '''INSERT INTO COMPANY (ID, NAME, AGE, ADDRESS, SALARY)
VALUES %s
'''
datalist = []
for i in range(1, 10000000):
# 生成6位随机字符串
name = ''.join(random.sample(string.ascii_letters + string.digits, 8))
age = random.randint(18, 80)
address = random.sample(address_list, 1)[0]
salary = random.randrange(5000, 100000)
# 行数据是以元组的形式存放
datalist.append((++i, name, age, address, salary))
extras.execute_values(cur, sql, datalist, page_size=20000)
conn.commit()
print("All records created successfully")
conn.close()