【Python 教程】PostgreSQL 工具类

安装psycopg2

pip install psycopg2-binary

创建 PostgreSQL 的工具类postgre_connection.py

import psycopg2


# 打开数据库
def open_db(host, user, password, dbname):
    return psycopg2.connect("host=" + host + " dbname=" + dbname + " user=" + user + " password=" + password)

# 获取游标
def get_cursor(db):
    return db.cursor()

# 执行 SQL 语句
def sql_commit(db, cursor, sql, param=None):
    try:
        # 执行sql语句
        cursor.execute(sql, param)
        # 提交到数据库执行
        db.commit()
        # 获取所有记录列表
        results = cursor.fetchall()
        return results
    except Exception as e:
        print(e)
        # 如果发生错误则回滚
        db.rollback()
        return None
    finally:
        cursor.close()
        db.close()

使用该工具类

from db.postgre_connection import open_db, get_cursor, sql_commit

if __name__ == "__main__":
    try:
        db = open_db('host', 'user', 'password', 'database')
        cursor = get_cursor(db)
        sql = "select * from users"
        user_list = sql_commit(db, cursor, sql)
        return user_list
    except Exception:
        print("数据库连接失败")
        return None