I have this:
$this->db->select('(select var_value from contents where table = "products" and table_id = products.id and var_name = "image" and name = "images" order by id asc limit 1) as main_picture');
$this->db->where('category_id', $cat)->from('products')->limit($limit, $start)->get();
The problem is that codeigniter is removing the "limit 1" inside the subquery...
Any advice?
Thx!
You can not use LIMIT inside $this->db->select(); method
Please refer to Active Record documentation
$this->db->get();
$this->db->get_where();
Are the only methods that allow the use of LIMIT
Related
The code below is what I have to get all the duplicated products (by title) and group them together. It works perfectly fine. However, I so many records in my Products table and getting all of them causes a performance issue. Is there a way this could be optimised to avoid getting all records and group them in one query? Thank you.
$products = Product::all();
$groupsOfProducts = $products->groupBy('title');
$duplicatedProductsGrouped = [];
foreach($groupsOfProducts as $productGroup) {
$productIsDuplicated = $productGroup->count() > 1;
if($productIsDuplicated) {
$duplicatedProductsGrouped[] = $productGroup;
}
}
var_dump($duplicatedProductsGrouped);
You can use having in the group by:
Product::groupBy('title')->having(DB::raw('count(*)'), ">", "1")->select('title')->get()
And you will get the titles of the duplicates, then you can query the database with those titles
EDIT:
Please also try and see if this is faster
Product::getQuery()->whereIn('title', array_column( DB::select('select title from products group by title having count(*) > 1'), 'title'))->get();
with this line you will get ONLY the products that has a duplicate title, and so your Collection groupby should be faster to aggregate the records by the title
Let your database do the work. When you call Product::all(), you're getting every single record, then making PHP do the rest. Change your query to something like the following:
Product::selectRaw("title, COUNT(*) AS count")->groupBy("title")->get();
The result will be a Collection of Product instances with a title and count attribute, which you can access and determine duplicated ones:
$products = Product::selectRaw("title, COUNT(*) AS count")->groupBy("title")->get();
$duplicatedProducts = collect([]);
foreach($products AS $product){
if($product->count > 1){
$duplicatedProducts->push($product);
}
}
dd($duplicatedProducts);
can I convert this query
"SELECT * FROM (SELECT * FROM blog_post ORDER BY data DESC) blog_post GROUP BY blog_id LIMIT 2"
into a Yii2 active record query?
Thx
Ms
Yes, you can do this.
Yii2 gave us a wonderful library support.
You can form custom sql query and pass this query in findBySql() like:
$sql = "Some query/nested query";
$result = ModelClass::findBySql($sql);
Visit Yii official documentation.
BlogPost::find()
->orderBy('data DESC')
->groupBy('blog_id')
->limit(2)
->all();
I suppose you can do in this way :
Ⅰ:create a subQuery where you select from.
$blogPostQuery = BlogPostModel::find()->orderBy(['data' => SORT_DESC]);
Ⅱ:Get activeRecord results. The from params is an exist Query.
$models = (new yii\db\Query)
->from(['blog_post ' => $blogPostQuery])
->groupBy(['blog_id'])
->limit(2)
->all();
ps:
see yii\db\query->from()-detail in Yii Api;
(public $this from ( $tables )) $tables can be either a string (e.g. 'user') or an array (e.g. ['user', 'profile']) specifying one or several table names··· or a sub-query or DB expression
Have a try!I hope it`s useful for you:))
I have the following query. Could you please tell me how to implement it in codeigniter.
SELECT mnu_name,mnu_desc,mnu_type FROM central_web_auth_mnu
WHERE mnu_name NOT IN(
SELECT mnu_name FROM central_web_auth_grp_mnu WHERE gr_id='.$grp.'
) ORDER BY mnu_desc;
Thank You.
$this->db->select('mnu_name, mnu_desc, mnu_type')->where('`mnu_name` NOT IN (SELECT `mnu_name` FROM `central_web_auth_grp_mnu` WHERE idgr_id= $grp)', NULL, FALSE)->order_by('mnu_desc', 'desc')->get('central_web_auth_mnu');
set false as third parameter so that escaping will skip:
CI active db library does support array params in where_in() or where_not_in() methods, so you can use where() method and pass condition as string, try this query
$this->db->select('mnu_name, mnu_desc, mnu_type')
->where('mnu_name NOT IN(SELECT mnu_name FROM central_web_auth_grp_mnu WHERE gr_id='.$grp.')')
->order_by('mnu_desc', 'desc')
->get('central_web_auth_mnu')
You can simply use codeigniter's Active Record library to achieve this (thanks Girish)
$this->db->select('mnu_name, mnu_desc, mnu_type')
->where('mnu_name NOT IN(SELECT mnu_name FROM central_web_auth_grp_mnu WHERE gr_id='.$grp.')')
->order_by('mnu_desc', 'desc');
$query = $this->db->get();
$num_rows = $query->num_rows();
Basicly i have two tables photos and users. I wanna join tables and Update colums image_max and image_min. I get error unknown colum username. In which way i can join two tabels and get data from both. My sintax is:
$this->db->select('*');
$this->db->from('photos');
$this->db->join('users', 'photos.id = users.id');
$this->db->where('username',$username);
$this->db->update('photos',$data);
And I get error
Unknown column username in where clause
UPDATE `photos` SET `image_max` = '', `image_min` = '' WHERE `username` = 'wwww'
apparently you need a letter on the table should say "users.username", check that.
Greetings.
$this->db->select('*');
$this->db->from('photos');
$this->db->join('users', 'photos.id = users.id');
$this->db->where('users.username',$username);
$this->db->update('photos',$data);
You don't need to use "select and from" before upload fields, just update in this way
$data = array('image_max'=> 4, 'image_min' => 1);
$this->db->join('users', 'photos.id = users.id');
$this->db->where('username',$username);
$this->db->update('photos',$data);
I have two tables books and authors. Using CodeIgniter I would like users to be able to Filter results - for example, show results where author_id = 'x' and book_lang = 'y' and publication_year = '2000'. Filter criteria values come from user via drop-downs.
What's the best way to generate the query using codeigniter helper and binding etc?
For example, the query below will give me everything with author_id= 1. what if filters are a mix, for example; author_id = 1; language = 'all' (don’t put where clause on language) and publication year = 'all' also don’t put where clause.. Do I manually need to check for values and code or is there a codigniter helper method that allows filter to be removed from where clause if dropdown value is 'show all'?
$sql = "select * from AUTHORs a , BOOKS b where
a.AUTH_ID = b.BOOK_AUTH_ID
and b.BOOK_AUTH_ID = ?
and b.BOOK_LANGUAGE = ?
and b.PUB_YEAR = ? ";
$query = $this->db->query($sql, array ($author_id, $book_lang, $pub_year));
You should use Codeigniter's Active Record class to construct your query:
$this->db->select('*');
$this->db->from('AUTHORs a , BOOKS b');
$this->db->where('a.AUTH_ID', 'b.BOOK_AUTH_ID');
if ($author_id != 'all') $this->db->where('b.BOOK_AUTH_ID', $author_id);
if ($book_lang != 'all') $this->db->where('b.BOOK_LANGUAGE', $book_lang);
if ($pub_year != 'all') $this->db->where('b.PUB_YEAR', $pub_year);
$query = $this->db->get();
To read more about Codeigniter's Active Record class, visit the Docs:
http://codeigniter.com/user_guide/database/active_record.html