我有四个表，每个表都与某个 id 连接，请参阅下面的查询我是如何得到的
SELECT
tax_rates.name,
IF( products.tax_method = 0, 'Inclusive', 'Exclusive') AS type,
IF((SUM(purchases.grand_total) > 0),(SUM(purchases.grand_total)),(SUM(purchase_items .subtotal))) AS total_amount,
IF((SUM(purchases.order_tax) > 0),(SUM(purchases.order_tax)),SUM(purchase_items .item_tax)) AS tax_amount
FROM tax_rates
LEFT JOIN purchases ON purchases.order_tax_id = tax_rates.id
LEFT JOIN purchase_items ON purchase_items.tax_rate_id = tax_rates .id
LEFT JOIN products ON products.id = purchase_items.product_id
WHERE purchases.warehouse_id = 1
GROUP BY tax_rates.id, products.tax_method
ORDER BY tax_rates.name desc LIMIT 0, 10
上面的查询没有返回任何结果，但如果我删除 WHEREpurchasing.warehouse_id = 1，那么它会显示结果。我不知道我哪里做错了。请纠正我。
很抱歉告诉您这一点，我正在尝试获取采购订单税和采购项目税 特别是商店和日期
输出
name type total_amount tax_amount
VAT @20% Inclusive 11005.2000 1834.2000
VAT @10% Inclusive 165.0000 15.0000
No Tax Exclusive 204771.4000 0.0000
GST @6% Exclusive 7155.0000 405.0000
GST @6% Inclusive 7155.0000 405.0000
谢谢
最佳答案
数据类型？ buys.warehouse_id = '1'?
关于MYSQL - JOIN 表过滤器不起作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37004162/