如何为PDO语句使用已定义的表名？

Question

I have in one of my config files all the table definitions, eg.

define('tbl_admin', 'site_admin');

I'm using PDO statement to get some values from the table, but i'm unable to call up the 'site_admin' table.

My code as follows:

      $db=new database();
      $pdo_db_connx=$db->PDO_database();          
      $smt=$pdo_db_connx->prepare("select id from tbl_admin where  admin=:username");
      $smt->bindParam(":username",$username);

Any advise please?

Answer 1

When you do:

$smt=$pdo_db_connx->prepare("select id from tbl_admin where  admin=:username");

tbl_admin is considered a table name tbl_admin, and not a constant.

The simpliest way is to concatenate parts of query with a constant:

$smt=$pdo_db_connx->prepare("select id from " . tbl_admin . " where  admin=:username");

Here, tbl_admin will be treated as constant and it's value will be used.