从3个表中选择数据限制

Question

I have 3 tables ppc_offers, survery_offers,find_offers ( from admin section, i enter data into these tables)

Now on front end, i want to display latest 3 offers from these tables.

ie latest 3 will come, they can be from single table or multiple tables... it just has condition "latest 3"

How can i do this?

Laravel provides any way to do this?

or do i need to have any master table?

or can you suggest me regular SQL query for this?

Please help. Thanks.

PPC Table:

-------------------------
id            |  integer
title         |  varchar
url           |  varchar
description   |  varchar
created_at    |  timestamp
updated_at    |  timestamp
--------------------------

survey Table:

-------------------------
id            |  integer
title         |  varchar
created_at    |  timestamp
updated_at    |  timestamp
--------------------------

find code Table:

-------------------------
id            |  integer
title         |  varchar
url           |  varchar
description   |  varchar
code          |  varchar
created_at    |  timestamp
updated_at    |  timestamp
--------------------------

Answer 1

Make 3 queries union them with the same names for columns

select * from

(
 (query1 order by id desc limit 3) x
   union
(query2 order by id desc limit 3) y
   union
(query3 order by id desc limit 3) z

(

Answer 2

As a recommendation, it might make more sense to include all 3 of these offers in one table, and use an "offer_type" id to distinguish them from each other, instead of using 3 different tables. It might simplify your code.

I believe this may work with your current setup:

$ppc = DB::table('ppc_offers')
  ->select('title', 'url', 'description', 'NULL as code', 'updated_at');

$survey = DB::table('survey_offers')
  ->select('title', 'NULL as url', 'NULL as description', 'NULL as code', 'updated_at');

$find = DB::table('find_offers')
  ->select('title', 'url', 'description', 'code', 'updated_at');

return $ppc->unionAll($survey)->unionAll($find)
  ->orderBy('updated_at', 'desc')
  ->take(3)
  ->get();