Im new to ruby on rails but trying to learn fast however i’ve hit a
roadblock. Im trying to do an sql statement in a view to get values from
a table however I have not been able to get get back just the values, I
seem to get the column names and the values as shown below.
seller_rating8advert_rating10commentGreat ad for that item of yours.
The line I am using to do this is
<%= rating = Product.connection.select_all("select comment,
seller_rating, advert_rating from ratings ")%>
I was also hoping to use the rating bit to print out the the values on
their own line for a row and then have a line and then print out the
next row as before.
e.g
seller ratting: 8
advert_rating: 10
comment: Great ad for that item of yours.
<%= rating = Product.connection.select_all("select comment,
seller_rating, advert_rating from ratings ")%>
Since you are just doing a database query and not getting any model
objects, you will get an array of hashes as the result. Each hash will
map the column name from your query to its value.
Your “<%=” then means output this value. When you ask Ruby to print a
hash, it just rubs together keys and values as you are seeing.
Firstly, you have model specific code in your view. If the ratings
table changes, you will need to hunt through your code for things like
this and change them.
If you have a ratings table, then do you not have a Ratings model? Why
use another model (Product) to look up a Rating? It looks like you
actually want your lookup to be:
Rating.find(:all)
Much simpler and no SQL.
Then you can go through then printing them out something like this:
<% Rating.find(:all) do |rating| %>
Seller rating: <% rating.seller_rating %>
Advert rating: <% rating.advert_rating %>
Comment: <% rating.comment %>
<% end %>
If you do find yourself needing to run SQL to get some results, decide
what model is best associated with the query and add a method to that
model to get the data. Then elsewhere, you just need to call that
method and use the results.
I should have explained what product is, I have two tables product has
product details and rating holds details for the product (users will
rate products). I want them to be able to move to a page and the comment
related to that pages item will appear.
e.g
Product’s details
Then comments from the rating table related will appear here.
Im only getting started with rails so I don’t know much about its ins
and outs. Im not sur how to do methods in models and the databases,
along with pages were created using scaffold.
<%= rating = Product.connection.select_all("select comment,
seller_rating, advert_rating from ratings ")%>
Since you are just doing a database query and not getting any model
objects, you will get an array of hashes as the result. Each hash will
map the column name from your query to its value.
Your “<%=” then means output this value. When you ask Ruby to print a
hash, it just rubs together keys and values as you are seeing.
Firstly, you have model specific code in your view. If the ratings
table changes, you will need to hunt through your code for things like
this and change them.
If you have a ratings table, then do you not have a Ratings model? Why
use another model (Product) to look up a Rating? It looks like you
actually want your lookup to be:
Rating.find(:all)
Much simpler and no SQL.
Then you can go through then printing them out something like this:
<% Rating.find(:all) do |rating| %>
Seller rating: <% rating.seller_rating %>
Advert rating: <% rating.advert_rating %>
Comment: <% rating.comment %>
<% end %>
If you do find yourself needing to run SQL to get some results, decide
what model is best associated with the query and add a method to that
model to get the data. Then elsewhere, you just need to call that
method and use the results.
I should have explained what product is, I have two tables product has
product details and rating holds details for the product (users will
rate products). I want them to be able to move to a page and the comment
related to that pages item will appear.
So your models are like this:
class Product < ActiveRecord::Base
has_many :ratings
end
class Rating < ActiveRecord::Base
belongs_to :product
end
?
In your Product show method, you are probably doing something like: