使用php / SQL從數據庫查詢信息

Question

我想使用這兩列從表中選擇數據。 我想做的是選擇表格，其中月份在2月和8 月之間， 年份在2003年和2005 年之間，包括2004年和2005年1月。

$number = range(3, 8);  

foreach($number as $key=> $value):
                    $where .= " Month ='$value' AND Year BETWEEN '2003' AND '2005' or " ;                   
        endforeach;
if(strlen(trim($where)) > 0)

    $where = substr(trim($where), 0, -2);`
$query = "SELECT * FROM myTable $where";

它返回以下查詢

SELECT * FROM myTable WHERE Month ='2' AND Year BETWEEN '2003' AND '2005' or Month ='3' AND Year BETWEEN '2003' AND '2005' or Month ='4' AND Year BETWEEN '2003' AND '2005' or Month ='5' AND Year BETWEEN '2003' AND '2005' or Month ='6' AND Year BETWEEN '2003' AND '2005' or Month ='7' AND Year BETWEEN '2003' AND '2005' or Month ='8' AND Year BETWEEN '2003' AND '2005'

但是我查詢的問題是它沒有選擇2004年和2005年1月。有人對如何執行此操作有想法嗎？

Answer 1

如下更改查詢。

SELECT * FROM myTable 
WHERE 
(Month ='2' AND Year BETWEEN '2003' AND '2005') 
or
( Month ='3' AND Year BETWEEN '2003' AND '2005')....

運算符的優先級確定表達式中項的求值順序 。 要顯式覆蓋此順序並將術語分組，請使用括號

Answer 2

SELECT * FROM myTable 
WHERE ( Month >=2 AND Month <=8 AND year BETWEEN 2003 AND 2005) OR (Month=1 AND (year=2004 OR year=2005))