使用SQL语句统计数据时sum和count函数中使用if判断条件的讲解

order_type：订单类型
open_id：用户唯一标识
SELECT
    date(create_time) AS '当天日期',
    sum(real_price) AS '当天总收入',
sum函数中使用if判断条件：{
sum(
IF (order_type = 0, real_price, 0)
) AS '当天支付收入',
sum(
IF (order_type = 1, real_price, 0)
) AS '当天打赏收入',
}
    count(DISTINCT open_id) AS '付费总人数',
count函数中使用if判断条件：{
count(
DISTINCT open_id,
IF (order_type = 0, TRUE, NULL)
) AS '支付人数',
count(
DISTINCT open_id,
IF (order_type = 1, TRUE, NULL)
) AS '打赏人数',
}
    count(id) AS '付费订单总数',
count函数中使用if判断条件：{
count(
DISTINCT id,
IF (order_type = 0, TRUE, NULL)
) AS '支付订单数',
count(
DISTINCT id,
IF (order_type = 1, TRUE, NULL)
) AS '打赏订单数'
}
FROM
orders
WHERE
'real_price' != 1
AND 'status' != 0
GROUP BY DATE(create_time)