Question

我如何为10,20,34和1的所有4个id执行select语句，并期望结果在列表中

import pymysql
import json

conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='', 
db='mydb', charset='utf8mb4', cursorclass=pymysql.cursors.DictCursor)

cursor = conn.cursor()

select_query = "select * from users where id = "
ids = ["10", "20", "34", "1"]
for x in ids:
    var = select_query + x
    # print(var)
    print(list(cursor.execute(var)))

Answer 1

根据PyMySQL docs，cursor.execute()函数返回int，这就是您的错误出现的原因。你想要调用它，然后使用其中一个fetch functions来实际返回结果

import pymysql

conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='',
                       db='mydb', charset='utf8mb4', cursorclass=pymysql.cursors.DictCursor)

cursor = conn.cursor()

select_query = "select * from users where id = "
ids = ["10", "20", "34", "1"]
for x in ids:
    var = select_query + x
    # print(var)
    cursor.execute(var)
    print(list(cursor.fetchall()))

或者，如果您希望将所有结果放在一个列表中：

import pymysql

conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='',
                       db='mydb', charset='utf8mb4', cursorclass=pymysql.cursors.DictCursor)

cursor = conn.cursor()

lst = []

select_query = "select * from users where id = "
ids = ["10", "20", "34", "1"]
for x in ids:
    var = select_query + x
    # print(var)
    cursor.execute(var)
    lst.extend(cursor.fetchall())

print(lst)

或作为字典

import pymysql

conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='',
                       db='mydb', charset='utf8mb4', cursorclass=pymysql.cursors.DictCursor)

cursor = conn.cursor()

results = {}

select_query = "select * from users where id = "
ids = ["10", "20", "34", "1"]
for x in ids:
    var = select_query + x
    # print(var)
    cursor.execute(var)
    results[x] = list(cursor.fetchall())

print(results)

Answer 2

您可能忘记将x转换为str

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python迭代sql查询select语句

2 个答案: