find_by_sql parameters

rubyonrails-talk
1

I am trying to run a pair of sql statements with the second using a value form the first's returned data set but can figure out the syntax.

@risks returns the values I would expect but @changes gets no returned data obvioulsy because it doesn't see the contenst of @risks.id.

def reportbyowner2 @risks = Risk.find_by_sql(["SELECT * FROM risks r where r.status = 'Open' and r.owner_id = ? order by r.id", @params['owner']]) @changes = Change.find_by_sql(["SELECT * FROM changes c where c.risk_id = ? order by c.id", @risks.id]) end

Any help please.

Many thanks.

2

I am trying to run a pair of sql statements with the second using a

value form the first’s returned data set but can figure out the syntax.

@risks returns the values I would expect but @changes gets no returned

data obvioulsy because it doesn’t see the contenst of @risks.id.

def reportbyowner2

@risks = Risk.find_by_sql(["SELECT * FROM risks r where r.status =

‘Open’ and r.owner_id = ? order by r.id", @params[‘owner’]])

@changes = Change.find_by_sql(["SELECT * FROM changes c where c.risk_id

= ? order by c.id", @risks.id])

How many records are there in the @risks object. You’re doing c.risk_id=@risks.id, so if there are multiple rows in @risks then the query wont return any result.

3

Shiv N Gautam wrote:

@changes = Change.find_by_sql(["SELECT * FROM changes c where c.risk_id = ? order by c.id", @risks.id])

How many records are there in the @risks object. You're doing c.risk_id=@ risks.id, so if there are multiple rows in @risks then the query wont return any result.

end

Any help please.

Many thanks. -- Posted via http://www.ruby-forum.com/.

>

Shiv,

The @risks object will have multiple risks. What I am trying to do is for each risk I select I print the risk details then go and get any changes records associted with that risk record and print them then go round again for the next risk.

Can you advise the syntax I would need to use to achieve this.

Much appreciated

Martyn

4

Shiv N Gautam wrote:

>> @changes = Change.find_by_sql(["SELECT * FROM changes c where c.risk_id >> = ? order by c.id", @risks.id])

> How many records are there in the @risks object. You're doing > c.risk_id=@ > risks.id, so if there are multiple rows in @risks then the query wont > return > any result.

>> end

>> Any help please.

>> Many thanks. >> -- >> Posted viahttp://www.ruby-forum.com/.

Shiv,

The @risks object will have multiple risks. What I am trying to do is for each risk I select I print the risk details then go and get any changes records associted with that risk record and print them then go round again for the next risk.

Can you advise the syntax I would need to use to achieve this.

I wouldn't use find_by_sql at all.

owner = Owner.find params[:owner] Changes.find_all_by_risk_id owner.open_risks

as long as owner has an open risks association like so

has_many :open_risks, :conditions => {:status => 'Open'}, :class_name => 'Risk'}

You could also do this with a named_scope.

Fred

5

I like using the ActiveRecord methods instead of raw sql, so here it goed: I assume that you have these 3 model: class Owner < ActiveRecord::Base    has_many :risks end class Risk < ActiveRecord::Base    belongs_to :owner    has_many :changes end class Change < ActiveRecord::Base    belongs_to :risk end

def reportbyowner2    @owner = Owner.find(params[:owner])    @risks = @owner.risks.all(:conditions => { :status => 'Open'})    @risks.each do |risk|         risk.print_the_details         risk.changes.each{|change| change.print_the_details }     end end

6

Thanks guys....your help was much appreciated!

Martyn