mysql条件忽略where子句

Question

I am trying to execute a mysql query in joomla where it takes a variable in where clause with the first item in drop-down is please select. I can set the value of drop-down to any value.

myquery is like this:

$db = JFactory::getDbo();
$m = $db->getQuery(true);
$m="SELECT group_concat(distinct m.email
SEPARATOR ', ' ) FROM member m, email e 
where m.club_name='{email___club_email}' ";
$db->setQuery($m);
$a = $db->loadresult();
var_dump($a);exit;
return $a;

Now How I should put a clause in this query so that If I select "please select" then the where clause in the statement is ignored or I can get all the records in any other manner in the resultset.

Answer 1

尝试类似where m.club_name LIKE '{email___club_email}'" ，并将”请选择“的value更改为%因为%是MySQL的通配符

Answer 2

您可以使用始终为true的内容，例如WHERE 1 = 1 ，这将返回所有记录。

Answer 3

You could set the value of the "please select" option as 0, and then do a simple if:

$m="SELECT group_concat(distinct m.email SEPARATOR ', ' ) FROM member m, email e"; 

if ($email) {
    $m .= " where m.club_name='{email___club_email}' ";
}