douming4359 2016-03-31 09:58
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检查值为null或不在条件MySQL的内部

I have a advanced search form which passes many variables to another page next.php.

My question is I want to check the variable is null or not inside query .

Can i use like this or is there any function like this??

$price=$_GET['price'];
$query="SELECT * FROM products WHERE (if price!='' { $price; } )";

Simply i want is if $price is null , i do not want check in where condition because it affects results.

How to do this guys??

Give me a solution

Thankss

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1条回答 默认 最新

  • doukun0888 2016-03-31 10:02
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    Just check BEFORE querying anything. Why would you waste time in generating query if you have nothing to generate with?

    $price=$_GET['price'];
    if($price !== NULL) {
       //do stuff
    }
    
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