Is it possible to, using only Rails, check first element in a join table?
Should be the same as:
User.includes(:articles).select {|u| !u.articles.first.voided? }
But with Rails 'where' statement is:
where("articles.first.status != 'voided'")
If your db is postgres and you can add first agg function than it should look like User.select('users.*').includes(:articles).group('users.id').where("FIRST(articles.status) != 'voided'")
Article.includes(:user).first.status
will give you first article status.try it pls
Related
i'm using node.js to build a web. I connect to my database (Mysql) and
get the data then return to the client side.
I know that i can use the literal template to write my sql expression like below
promise(`SELECT table.name FROM table WHERE name = ?`,[parameter])
and i'm would like to know can i write my sql expression like this?
promise(`SELECT table.? FROM table`,[parameter])
I know the result is different, i just want to know it is right or not.
thank you and have a nice day.
No, but you could use string interpolation like:
promise(`SELECT table.name FROM table WHERE name = ${parameter}`)
I'm trying to add a condition for the xml_sitemap table in a query to exclude any "loc" field that starts with node/. This is what I have below. I do not think this is working correctly.
$query->condition('loc', 'node/%', 'NOT LIKE');
I found it. The xml_sitemap module needs to be hacked directly xml_sitemap.generate.inc for this: $link_url = url($link['loc'], $link_options + $url_options);
I am working on a problem where I need to add an OR clause to a set of existing conditions. The current conditions are built in a hash in a method and at the end, they are used in the where clause. Here is a simplified example:
...
conds.merge!({:users => {:archived => false}})
Model.where(conds)
I am trying to add an OR clause to the current set of conditions so it would be something like '(conditions) OR new_condition'. I'd like to add the OR statement without converting each addition to the conds hash into a string. That would be my last option. I was hoping someone has done something like this before (without using Arel). I seem to recall in Rails 2 there was a way to parse a conditions hash using a method from the model (something like Model.some_method(conds) would produce the where clause string. Maybe that would be a good option to just add the OR clause on to that string. Any ideas are appreciated. Thank you for your help!
I found a way to do what I needed. Instead of changing all of the conditions that I am building, I am parsing the conditions to SQL using sanitize_sql_for_conditions. This is a private method in ActiveRecord, so I had to put a method on the model to allow me to access it. Here is my model method:
def self.convert_conditions_hash_to_sql(conditions)
self.sanitize_sql_for_conditions(conditions)
end
So, once I convert my conditions to text, I can add my OR clause (along with the appropriate parentheses) to the end of the original conditions. So, it would go something like this:
Model.where('(?) OR (model.type = ? AND model.id IN(?))', Model.convert_conditions_hash_to_sql(conds), model_type, model_id_array)
I'm using Rails 3 with a MySQL database, and I need to programmatically create a query like this:
select * from table where category_name like '%category_name_1%'
OR category_name like '%category_name_2%'
(...snip...)
OR category_name like '%category_name_n%'
Given the table size and the project scope (500 rows at most, I think), I feel that using something like thinking sphinx would be overkill.
I know I could simply do this by writing the query string directly, but wanted to know if there's an ActiveRecord way to do this. There's no mention of this on the official guide, and I've been googling for a long while now, just to end empty-handed :(
Also, is there a reason (maybe a Rails reason?) to not to include the OR clause?
Thanks!
Assuming you have an array names with category names:
Model.where( names.map{"category_name LIKE ?"}.join(" OR "),
*names.map{|n| "%#{n}%" } )
you should google first, there is already an answer.
Look here and then here
and you'll get something like this:
accounts = Account.arel_table
Account.where(accounts[:name].matches("%#{user_name}%").or(accounts[:name].matches("%#{user_name2}%")))
If you look at the guide, they have examples that can easily be modified to this:
Client.where("orders_count = ? OR locked = ?", params[:orders], false)
Mysql has a regexp function now that can clean things up a bit, assuming there's no regex metachars in your category names:
Table.where "category_name regexp '#{names.join('|')}'"
I want to run a query like this:
SELECT * FROM table WHERE field LIKE '%search_term%'
In CI you can bind parameters to queries, if you used field=? but this does not work for field LIKE "%?%". From debugging output it seems the query used is field LIKE "%'search'%".
Is there an alternative way to do searching in CodeIgniter?
You can use this query:
SELECT * FROM table WHERE field LIKE ?
And bind with %search% instead of search.
You should be aware that this query will be slow in MySQL. You might want to look at free-text search instead (Lucene, Sphinx, or MySQL's built-in free-text search functions).
this is active record class for codeigniter
$this->db->select('*');
$this->db->like('columnname','both');
$query=$this->db->get("tablesname");
$result=$query->result_array();
if(count($result))
{
return $result;
}
else
{
return FALSE;
}
You should try this..I think its help you..
both means %columnname%,
before means %columnname,
after means columnname%
$search_term=$this->input->post('textboxName');
$search_term="%".$search_term."%";
$sql="SELECT * FROM table WHERE field LIKE ? ";
$query=$this->db->query($sql,array($search_term));
$res=$query->result();
what i can understand CI is adding quotes, pass FALSE as third parameter while binding to prevent CI adding quotes.