schema builder laravel migrations unique on two columns

Question

How can I set a unique constraints on two columns?

class MyModel extends Migration {
  public function up()
  {
    Schema::create(\'storage_trackers\', fun         


        

Answer 1

DB::statement("ALTER TABLE `project_majr_actvities`
               ADD UNIQUE `unique_index`(`activity_sr_no`, `project_id`)");

Answer 2

The second param is to manually set the name of the unique index. Use an array as the first param to create a unique key across multiple columns.

$table->unique(array('mytext', 'user_id'));

or (a little neater)

$table->unique(['mytext', 'user_id']);

Answer 3

Simply you can use

$table->primary(['first', 'second']);

Reference: http://laravel.com/docs/master/migrations#creating-indexes

As an example:

    Schema::create('posts_tags', function (Blueprint $table) {

        $table->integer('post_id')->unsigned();
        $table->integer('tag_id')->unsigned();

        $table->foreign('post_id')->references('id')->on('posts');
        $table->foreign('tag_id')->references('id')->on('tags');

        $table->timestamps();
        $table->softDeletes();

        $table->primary(['post_id', 'tag_id']);
    });