使用MySQL的PHP​​中的搜索引擎：无法使用多个关键字进行搜索，出现PDOException错误

Question

I must say am still a baby when it comes to php and mysql, but am learning and improving everyday with you guys help. Yeah I created a search engine in PHP with MySQL and to an extent, it is working, but the challenge that am having is that I get PDOException error message when i search with more than a single keyword like 'David Smith' but with 'David' or 'Smith' alone, i don't get any error.

Honestly I don't know where I got it all wrong. Am using wampserver PDO db connection for my Database. below is the sample of the code.

    //search button name and id is 'search'

    $search_exploded = explode (" ", $search);

    foreach($search_exploded as $search_each)
        {
            for($x=0; $x<=0; $x++ ); 

            if($x==1)
                $construct .="UserID LIKE '%$search_each%' or Requestor LIKE '%$search_each%' or EmploymentType LIKE '%$search_each%'";
            else
                $construct .="AND UserID LIKE '%$search_each%' AND Requestor LIKE '%$search_each%' AND EmploymentType LIKE '%$search_each%'"; 
        }
    $sql = "SELECT COUNT(*) as num FROM ".TBL_STUDENTS." WHERE $construct";
    $result = $database->connection->prepare($sql);
    $result->execute(array($construct)); 

Like i said, it works fine when i search with a single keyword like 'David' but i get error when i search with something like 'David Smith'.

Below is the error message that I do get:

Fatal error: Uncaught exception '`PDOException`' with message '`SQLSTATE[42000]`:
Syntax error or access violation: 1064 You have an error in your SQL syntax;
check the manual that corresponds to your MySQL server version for the right syntax
to use near 'UserID LIKE '%Gift%' or Requestor LIKE `%Gift%` or EmploymentType LIKE `%Gift%` at line 3'
in `C:\wamp\www\ccnl\script\search_db.php` on line 108

The line is this code below

$result->execute(array($construct)); 

Answer 1

Try using an array, then imploding it:-

//search button name and id is 'search'

$search_exploded = explode (" ", $search);

$construct = array();

foreach($search_exploded as $search_each)
{
    $construct[] =" (UserID LIKE '%$search_each%' or Requestor LIKE '%$search_each%' or EmploymentType LIKE '%$search_each%') ";
}
$sql = "SELECT COUNT(*) as num FROM ".TBL_STUDENTS." WHERE ".implode(" OR ", $construct);
$result = $database->connection->prepare($sql);
$result->execute(array($construct));

Answer 2

Put a space

$construct .="AND Use

in front of AND like this:

$construct .=" AND Use