psycopg2.ProgrammingError：列“ none”不存在-更新語句

Question

我一直遇到錯誤“ psycopg2.ProgrammingError：列“ none”不存在”。

我已經閱讀了psycopg2文檔並查看了有關此錯誤的其他文章，但是，許多文章特定於插入查詢而不是更新查詢 。

我的代碼如下：

def send_to_sql(identity,list1,list2,list3):
    userid = 30
    Fixture_No = None
    Home_Side_Score = None
    Away_Side_Score = None
    conn = psycopg2.connect("dbname='Euro2016' user='postgres' host='localhost' password='##passwordhere##'")
    cur = conn.cursor()
    cur.execute("""UPDATE "Predictions" SET userid = %r, "Fixture_No" = %r, "Home_Side_Score" = %r, "Away_Side_Score" = %r WHERE "Predictions"."userid" = %r AND "Predictions"."Fixture_No" = %r """ % (userid, Fixture_No, Home_Side_Score, Away_Side_Score, userid, Fixture_No))
    conn.commit()
    cur.close()
    conn.close()

如果我要傳遞的分數和固定裝置編號是數字，則此代碼可以正常工作，但是當輸入None時，代碼就會掉在臉上。 有人救了我...

Answer 1

使用%s而不是%r 。 要檢查發送到服務器的內容，請使用cursor. mogrify cursor. mogrify

update = """
    UPDATE "Predictions"
    SET 
        userid = %s, 
        "Fixture_No" = %s, 
        "Home_Side_Score" = %s, 
        "Away_Side_Score" = %s
    WHERE 
        "Predictions"."userid" = %s AND 
        "Predictions"."Fixture_No" = %s
"""
data = (userid, Fixture_No, Home_Side_Score, Away_Side_Score, userid, Fixture_No)
print cur.mogrify(update, data)
cur.execute(update, data)

更好的是，使用字典來傳遞數據：

update = """
    UPDATE "Predictions"
    SET
        userid = %(userid)s, 
        "Fixture_No" = %(Fixture_no)s,
        "Home_Side_Score" = %(Home_Side_Score)s,
        "Away_Side_Score" = %(Away_Side_Score)s
    WHERE
        "Predictions"."userid" = %(userid)s AND
        "Predictions"."Fixture_No" = %(Fixture_No)s
"""
data = dict (
    userid = userid,
    Fixture_No = Fixture_No,
    Home_Side_Score = Home_Side_Score,
    Away_Side_Score = Away_Side_Score
)