SQL Select Distinct仍显示重复项

Question

我使用该DISTINCT子句有以下查询,但结果仍然显示重复的ID:

SELECT DISTINCT 
    rl.countryid, rl.resellerid, c.countryname, c.iso2, r.resellerid 
FROM reseller_locator rl 
INNER JOIN countries c 
    ON rl.countryid = c.countryid
LEFT JOIN resellers r 
    ON r.parentid = 7 
WHERE 
    rl.resellerid = 7 
    OR rl.resellerid = r.resellerid

Answer 1

DISTINCT涉及指定的所有列,因此如果您有2个相同countryid但不同的记录,则resellerid两者都会显示.