Laravel - Union + Paginate at the same time?

Question

Brief:

I am trying to union 2 tables recipes and posts then add ->paginate(5) to the queries.

But

Answer 1

I know this answer is too late. But I want to share my problems and my solution.

My problems:

1. Join with many tables at the same time
2. UNION
3. Paginate (Must use, because I have to use a common theme to show pagination. If I made own custom for pagination, it will not match to current. And in the future, a common theme may be changed.)
4. Big data: view took 4 seconds, page load took 4 seconds => total is 8 seconds. (But if I set condition inside that view, it was least than 1 second for total.)

Query

※This is the sample. MariaDB, about 146,000 records.

SELECT A.a_id
     , A.a_name
     , B.organization_id
     , B.organization_name
  FROM customers A 
    LEFT JOIN organizations B ON (A.organization_id = B.organization_id)

UNION ALL

SELECT A.a_id
     , A.a_name
     , B.organization_id
     , B.organization_name
  FROM employees A 
    LEFT JOIN organizations B ON (A.organization_id = B.organization_id)

Solution

Reference from www.tech-corgi.com (やり方２), I updated my PHP code to filter inside my query, and then call paginate normally.

I must add a condition (filter) before getting large records. In this example is organization_id.

$query = "
    SELECT A.a_id
         , A.a_name
         , B.organization_id
         , B.organization_name
      FROM customers A 
        LEFT JOIN organizations B ON (A.organization_id = B.organization_id)
     WHERE 1 = 1
       AND B.organization_id = {ORGANIZATION_ID}

    UNION ALL

    SELECT A.a_id
         , A.a_name
         , B.organization_id
         , B.organization_name
      FROM employees A 
        LEFT JOIN organizations B ON (A.organization_id = B.organization_id)

     WHERE 1 = 1
       AND B.organization_id = {ORGANIZATION_ID}
";

$organization_id = request()->organization_id;
$query = str_replace("{ORGANIZATION_ID}", $organization_id, $query);

But it still cannot be used in paginate(). There is a trick to solve this problem. See below.

Final code

Trick: put query inside (). For example: (SELECT * FROM TABLE_A).

Reason: paginage() will generate and run Count query SELECT count(*) FROM (SELECT * FROM TABLE_A), if we did not put inside brackets, Count query would not be a correct query.

$query = "
    ( SELECT A.a_id
         , A.a_name
         , B.organization_id
         , B.organization_name
      FROM customers A 
        LEFT JOIN organizations B ON (A.organization_id = B.organization_id)
     WHERE 1 = 1
       AND B.organization_id = {ORGANIZATION_ID}

    UNION ALL

    SELECT A.a_id
         , A.a_name
         , B.organization_id
         , B.organization_name
      FROM employees A 
        LEFT JOIN organizations B ON (A.organization_id = B.organization_id)

     WHERE 1 = 1
       AND B.organization_id = {ORGANIZATION_ID}
    ) AS VIEW_RESULT
";

$organization_id = request()->organization_id;
$query = str_replace("{ORGANIZATION_ID}", $organization_id, $query);

$resultSet = DB::table(DB::raw($query))->paginate(20);

Now I can use it normally:

1. SELECT, JOIN, UNION
2. paginate
3. High performance: Filter data before getting

Hope it help!!!