sql根据条件查询,没有记录的时候为什么返回的是null,应该是一个[]。
SELECT
city AS city,
brandname AS brandname,
citylevel AS citylevel,
SUM(ordercount) AS ordercount,
SUM(paytransaction) AS paytransaction
FROM
b_basis cb
WHERE cb.brandname = 'xxxx' AND cb.city = 'xxx' ORDER BY SUM(ordercount) DESC limit 0,15;
[{
"city" :null,
"brandname" :null,
"citylevel" :null,
"ordercount" :null,
"paytransaction" :null
}]