Laravel's database query builder provides a convenient, fluent interface to creating and running database queries.
- It uses PDO parameter binding to protect your application against SQL injection. There is no need to clean strings passed as bindings.
Joins
To perform a basic "
inner join", you may use the
join() method on a query builder instance.
The first argument is the name of the table you need to join to; the remaining arguments specify the relation of the columns for the join.
- You can join to multiple tables in a single query:
$users = DB::table('users')
->join('contacts', 'users.id', '=', 'contacts.user_id')
->join('orders', 'users.id', '=', 'orders.user_id')
->select('users.*', 'contacts.email', 'orders.price')
->get();
- To perform a "
left join" query, use the
leftJoin() method, in the same way as the
join() method.
$users = DB::table('users')
->leftJoin('posts', 'users.id', '=', 'posts.user_id')
->get();
Unions
To "
union" two queries together, create an initial query and use the
union() method to union it with a second query.
$first = DB::table('users')->whereNull('first_name');
$users = DB::table('users')->whereNull('last_name')
->union($first)->get();
- Documentation:
Laravel - Database: Query Builder
Daily Test with Code Example
HTML
CSS
JavaScript
PHP-MySQL
Which tag adds an image in web page?
<div> <img> <span><img src="http://coursesweb.net/imgs/webcourses.gif" width="191" height="63" alt="Courses-Web" />
Which of these CSS codes displays the text oblique?
font-style: italic; text-decoration: underline; font-weight: 500;#id {
font-style: italic;
}
Click on the jQuery function used to hide with animation a HTML element.
click() hide() show()$(document).ready(function() {
$(".a_class").click(function(){ $(this).hide("slow"); });
});
Click on the correctly defined function in PHP.
fname function() {} function fname() {} function $fname() {};function fname($a, $b) {
echo $a * $b;
}