0
這很好,但現在我想加入第三張名爲「房屋」的表格。但前提是houses.owner
等於p.id
。如果沒有houses.owner
等於p.id
不選擇。UNION的問題MySQL
當前SQL的作品
-- Select player AND if he is member of a guild then get rank and guild
SELECT p.id, p.account_id, p.group_id, p.name, p.sex, p.level, p.vocation, p.town_id, p.lastlogin, p.comment, p.deleted, p.online, p.rank_id, gr.name AS rank, g.name AS guild
FROM players p
INNER JOIN guild_ranks gr ON gr.id = p.rank_id
INNER JOIN guilds g ON g.id = gr.guild_id
WHERE p.name = :name and p.rank_id > 0
UNION ALL
SELECT p.id, p.account_id, p.group_id, p.name, p.sex, p.level, p.vocation, p.town_id, p.lastlogin, p.comment, p.deleted, p.online, p.rank_id, '' AS rank, '' AS guild
FROM players p
WHERE p.name = :name AND p.group_id < 5 AND p.rank_id = 0
我曾嘗試加入:
,但它給了我:
The used SELECT statements have a different number of columns
我希望你需要將空白字符串轉換爲與第一個查詢相同的數據類型。 – 2014-10-30 20:39:47
排除所有列,然後慢慢地將它們添加回來進行故障排除。從文字'1'開始,然後使用p.id,然後使用p.id,p.account_id等,直到查詢中斷。 – 2014-10-30 20:46:26