SELECT
tba.UpdatedDate AS UpdatedDate,
tsh.SupplierID,
ts.ProductCode as ProductCode,
sum(tba.AfterDiscount) as AfterDiscount,
sum(tba.Quantity) as Quantity
FROM
tblstockhistory as tsh
left join tblstock as ts
on tsh.StockID=ts.StockID
left join tblbasket as tba
on ts.ProductCode=tba.ProductCode
and tsh.SupplierID=49
AND tba.Status=3
group by
tba.UpdatedDate
ORDER BY
Quantity DESC
我有供應商表,供應商ID標記在給tblstockhistory表,並且在這種tblstockhistory表包含StockID(從tblstock表引用),我有庫存表包含StockID ,產品代碼, 和我有tblbasket表,在此我保持了產品代碼,MySQL的組加入
我的想法在這裏, 我想說明的供應商ID,當我通過供應商ID,它展示秀THW統計,這個供應商提供商品銷售統計,
但上面的查詢有時會返回空值,它需要太多的時間excution,約50秒,
我是什麼樣的財產以後下面從上面查詢
Date SupplierID, Amount, Quantity
2010-12-12 12 12200 20
2010-12-12 40 10252 30
2010-12-12 10 12551 50
2010-12-13 22 1900 20
2010-12-13 40 18652 30
2010-12-13 85 19681 50
2010-12-15 22 1900 20
2010-12-15 40 18652 30
2010-12-15 85 19681 50
爲了提高性能,請確保您在連接中使用的所有字段都已編入索引。 – Nazariy 2010-12-13 17:23:37