queryAPI.php

<?php

    public function testRepoFetchColumn()
    {
        $this->assertResultSuccess(Book::create([ 'title' => 'Book 1' ]));
        $this->assertResultSuccess(Book::create([ 'title' => 'Book 2' ]));

        // create one book with duplicated title
        $this->assertResultSuccess(Book::create([ 'title' => 'Book 2' ]));

        $q = Book::masterRepo()->select('DISTINCT title');
        $titles = $q->fetchColumn(0);
        $this->assertCount(2, $titles);

        foreach ($titles as $title) {
            $this->assertStringMatchesFormat('Book %i', $title);
        }
    }