Question

我正在运行以下版本的软件：

Python 3.5
psycopg2==2.6.1
Postgres 9.4.5

我有2张桌子。表User包含UserId (serial PK)，LastName，FirstName，Gender，DateOfBirth和DateEnrolled。表UserProfile包含UserProfileId (serial, PK)，UserId (FK)，DateEntered，FaveNumber和Activity。有一对多的关系。

以下PostgreSQL可以工作并最终在UserProfile中创建一个带有关联UserId（FK）的记录。

\set last_name '''Sara'''
\set first_name '''Jackson'''
\set gender '''F'''
\set dob '''1941-1-12'''
\set fave_number '''3''' 
\set activity '''volleyball'''


WITH ins_user AS (
INSERT INTO User
(LastName, FirstName, Gender, DateOfBirth, DateEnrolled)
VALUES (:last_name, :first_name, :gender, :dob, now())
RETURNING UserId)
INSERT INTO UserProfile
(UserId, DateEntered, FaveNumber, Activity) 
VALUES ( (SELECT UserId FROM ins_user), now(), :fave_number :activity);

如何构建一个能完成上述PostgreSQL的psycopg2 cur.execute查询？我已经阅读了文档，但似乎无法理解我应该如何构建此命令。

我的出发点是：

cur.execute( \
"""INSERT INTO User \
(LastName, FirstName, Gender, DateOfBirth, DateEnrolled) \
VALUES (%s, %s, %s, %s, %s) RETURNING UserId;""", \
(last_name, first_name, gender, date_of_birth, now(), ??...??)

此外，是否可以提取从RETURNING UserId派生的值，以便可以在以后的查询中使用？

感谢您的时间！

Answer 1

使用字典传递参数

更清楚

ins = """
    with ins_user as (
        insert into User (
            LastName, FirstName, Gender, DateOfBirth, DateEnrolled
        ) values (%(last_name)s, %(first_name)s, %(gender)s, %(dob)s, now())
        returning UserId
    )
    insert into UserProfile (
        UserId, DateEntered, FaveNumber, Activity
    ) values ((select UserId from ins_user), now(), %(fave_number)s, %(activity)s)
"""

ins_dict = dict (
    last_name = 'Sara',
    first_name = 'Jackson',
    gender = 'F',
    dob = '1941-1-12',
    fave_number = '3',
    activity = 'volleyball'
)
print cur.mogrify(ins, ins_dict) # inspect the rendered command
cur.execute(ins, ins_dict)
connection.commit()

如果DateEnrolled始终收到now()，请将其设为默认

DateEnrolled date default now(),

Answer 2

cur.execute( \
"""INSERT INTO User \
(LastName, FirstName, Gender, DateOfBirth, DateEnrolled) \
VALUES (%s, %s, %s, %s, %s) RETURNING UserId;""", \
(last_name, first_name, gender, date_of_birth, now(), ??...??)

Psycopg2使用外键创建记录

2 个答案: