convert SQL query to query builder style - php

Question

Im trying days to understand how I can convert a SQL query to a query builder style in laravel.
My SQL query is:
$tagid = Db::select("SELECT `id` FROM `wouter_blog_tags` WHERE `slug` = '".$this->param('slug')."'");
$blog = Db::select("SELECT *
FROM `wouter_blog_posts`
WHERE `published` IS NOT NULL
AND `published` = '1'
AND `published_at` IS NOT NULL
AND `published_at` < NOW()
AND (
SELECT count( * )
FROM `wouter_blog_tags`
INNER JOIN `wouter_blog_posts_tags` ON `wouter_blog_tags`.`id` = `wouter_blog_posts_tags`.`tags_id`
WHERE `wouter_blog_posts_tags`.`post_id` = `wouter_blog_posts`.`id`
AND `id`
IN (
'".$tagid[0]->id."'
)) >=1
ORDER BY `published_at` DESC
LIMIT 10
OFFSET 0");
Where I now end up to convert to the query builder is:
$test = Db::table('wouter_blog_posts')
->where('published', '=', 1)
->where('published', '=', 'IS NOT NULL')
->where('published_at', '=', 'IS NOT NULL')
->where('published_at', '<', 'NOW()')
->select(Db::raw('count(*) wouter_blog_tags'))
->join('wouter_blog_posts_tags', function($join)
{
$join->on('wouter_blog_tags.id', '=', 'wouter_blog_posts_tags.tags_id')
->on('wouter_blog_posts_tags.post_id', '=', 'wouter_blog_posts.id')
->whereIn('id', $tagid[0]->id);
})
->get();
I have read that I can't use whereIn in a join. The error i now get:
Call to undefined method Illuminate\Database\Query\JoinClause::whereIn()
I realy dont know how I can convert my SQL to query builder. I hope when I see a good working conversion of my query I can understand how I have to do it next time.

Answer 1

This work for me:
DB::table('wouter_blog_posts')
->whereNotNull('published')
->where('published', 1)
->whereNotNull('published_at')
->whereRaw('published_at < NOW()')
->whereRaw("(SELECT count(*)
FROM wouter_blog_tags
INNER JOIN wouter_blog_posts_tags ON wouter_blog_tags.id = wouter_blog_posts_tags.tags_id
WHERE wouter_blog_posts_tags.post_id = wouter_blog_posts.id
AND id
IN (
'".$tagid."'
)) >=1")
->orderBy('published_at', 'desc')
->skip(0)
->take(10)
->paginate($this->property('postsPerPage'));

Answer 2

The following Query Builder code will give you the exact SQL query you have within your DB::select:
DB::table('wouter_blog_posts')
->whereNotNull('published')
->where('published', 1)
->whereNotNull('published_at')
->whereRaw('`published_at` < NOW()')
->where(DB::raw('1'), '<=', function ($query) use ($tagid) {
$query->from('wouter_blog_tags')
->select('count(*)')
->join('wouter_blog_posts_tags', 'wouter_blog_tags.id', '=', 'wouter_blog_posts_tags.tags_id')
->whereRaw('`wouter_blog_posts_tags`.`post_id` = `wouter_blog_posts`.`id`')
->whereIn('id', [$tagid[0]->id]);
})
->orderBy('published_at', 'desc')
->skip(0)
->take(10)
->get();
The subquery condition had to be reversed because you can't have a subquery as the first parameter of the where method and still be able to bind the condition value. So it's 1 <= (subquery) which is equivalent to (subquery) >= 1. The query generated by the above code will look like this:
SELECT *
FROM `wouter_blog_posts`
WHERE `published` IS NOT NULL
AND `published` = 1
AND `published_at` IS NOT NULL
AND `published_at` < Now()
AND 1 <= (SELECT `count(*)`
FROM `wouter_blog_tags`
INNER JOIN `wouter_blog_posts_tags`
ON `wouter_blog_tags`.`id` =
`wouter_blog_posts_tags`.`tags_id`
WHERE `wouter_blog_posts_tags`.`post_id` =
`wouter_blog_posts`.`id`
AND `id` IN ( ? ))
ORDER BY `published_at` DESC
LIMIT 10 offset 0
My process when creating more complex queries is to first create them and try them out in a SQL environment to make sure they work as indended. Then I implement them step by step with the Query Builder, but instead of using get() at the end of the query, I use toSql() which will give me a string representation of the query that will be generated by the Query Builder, allowing me to compare that to my original query to make sure it's the same.