如何在数据库中为 INT 插入 null 值？

Question

I am not using HTML form to get values for this query. I am just inserting a second query once user creates a specific record. However, the second query is not inserting '0' unless I change it to VARCHAR. Others are working fine except for number.

$null = null;
    $query2="insert into npi_program2 (prodID,prodName,TPM,scheme,phases,status,number,date,remarkProg) 
             values('$prodID','$prodName','$null','$null','$null', 0 ,DATE_FORMAT(NOW(),'%b-%d-%Y'),'$null')";
    
    $res1=$db->query($query2);

Answer 1

0 is not equal to null. 0 is false. To insert null in the database, you should pass NULL as a value.

    $query2="insert into npi_program2 (prodID,prodName,TPM,scheme,phases,status,number,date,remarkProg) 
             values($prodID,$prodName,NULL,NULL,NULL, 0 ,DATE_FORMAT(NOW(),'%b-%d-%Y'),NULL)";
    
    $res1=$db->query($query2)