我在數據庫表中有一個列名'AmountLC'。另一列名稱'DebitCredit'確定'AmountLC'是正值還是負值。如果DebitCredit =「H」,則AmountLC中的值爲負值。如果DebitCredit =「S」,則AmountLC中的值爲正值。我需要查詢才能獲得AmountLC的總和。我試圖得到邏輯,但沒有得到任何。如果有人能幫助我,我將不勝感激。MYSQL SUM的正負值
我嘗試了下面的代碼,根據其他stackoverflow討論。
$F7 = mysql_query("SELECT
SUM(CASE WHEN DebitCredit='H' THEN DebitCredit ELSE 0 END) as NegativeTotal,
SUM(CASE WHEN DebitCredit='S' THEN DebitCredit ELSE 0 END) as PostiveTotal
FROM T1_CSV_Table
WHERE Month='$getMonth' AND TaxCode='A0'");
謝謝! 更新代碼的結果
$F7 = mysql_query("SELECT
SUM(CASE WHEN DebitCredit='H' THEN AmountLC*-1 ELSE AmountLC END) as Total
FROM T1_CSV_Table
WHERE Month='$getMonth' AND TaxCode='A0'");
$rowf7 = mysql_fetch_array($F7);
echo "Total-".$rowf7['Total'];
更新代碼: 選擇AmountLC
,DebitCredit
FROM T1_CSV_Table
WHERE TaxCode
= 「A0」 和月= 「12」
每次你使用【了'mysql_'(http://stackoverflow.com/questions/12859942/why-shouldnt-i-use-mysql-functions-in-php) dat在新代碼基礎上擴展 ** [小貓在世界的某個地方被勒死](http://2.bp.blogspot.com/-zCT6jizimfI/UjJ5UTb_BeI/AAAAAAAACgg/AS6XCd6aNdg/s1600/luna_getting_strangled.jpg)**它是已棄用並已使用多年,並在PHP7中永遠消失。 如果您只是學習PHP,花費精力學習'PDO'或'mysqli'數據庫擴展和準備語句。 [從這裏開始](http://php.net/manual/en/book.pdo.php) – RiggsFolly
不應該'那麼DebitCredit'是'THEN AmountLC'? – Barmar
'SUM(CASE WHEN DebitCredit ='H'THEN AmountLC * -1 ELSE AmountLC END)as Total,' – RiggsFolly