Ruby sql question

[Manish Sharma]

Hi,

Im using ActiveRecord to find something.

<% @new = User.find_by_sql("SELECT * FROM users WHERE users.id NOT IN
(array)") %>

Now, i can't seem to make it look through the array. I had a look for
this problem in other languages and in php its simply $array.

 

[Leslie Viljoen]

Hi,

Im using ActiveRecord to find something.

<% @new = User.find_by_sql("SELECT * FROM users WHERE users.id NOT IN
(array)") %>

Now, i can't seem to make it look through the array. I had a look for
this problem in other languages and in php its simply $array.

Perhaps:
"SELECT * FROM users WHERE users.id NOT IN (#{array.join(', ')})"

 

[Manish Sharma]

Perhaps:
"SELECT * FROM users WHERE users.id NOT IN (#{array.join(', ')})"

Thank you Leslie. That worked fine.

 

[Manish Sharma]

Perhaps:
"SELECT * FROM users WHERE users.id NOT IN (#{array.join(', ')})"

Just an extra question though. what does the array.join(',') do?

 

[Josh Cheek]

[Note: parts of this message were removed to make it a legal post.]

Just an extra question though. what does the array.join(',') do?

http://www.ruby-doc.org/core/classes/Array.html#M002182

Returns a string created by converting
each<http://www.ruby-doc.org/core/classes/Array.html#M002173>element
of the array to a string, separated by
*sep*.

[ "a", "b", "c" ].join #=> "abc"
[ "a", "b", "c" ].join("-") #=> "a-b-c"


Also, your use of erb and ActiveRecord implies a MVC structure. If this is
the case, you should be assigning instance variables in your controller and
not your view. You should not have find statements or assignments in your
view, it should only be for formatting output.

 

[Leslie Viljoen]

Just play around with it in IRB:

irb(main):002:0> ['a', 'b', 'c'].join(',')
=> "a,b,c"

I think that when PHP converts $array to a string, it puts commas in
between each element, which is just lucky for the purposes of
producing a list that the SQL statement would like.

This is what happens when Ruby converts an array to a string:
irb(main):003:0> ['a', 'b', 'c'].to_s
=> "abc"

So to put in the commas like PHP does it (and SQL likes it), use join.

 

[Matt Haley]

Hi,

Im using ActiveRecord to find something.

<% @new = User.find_by_sql("SELECT * FROM users WHERE users.id NOT IN
(array)") %>

With ActiveRecord you can use:

User.allconditions => ["users.id NOT IN (?)", array])

 

[Rajinder Yadav]

Hi,

Im using ActiveRecord to find something.

<% @new = User.find_by_sql("SELECT * FROM users WHERE users.id NOT IN
(array)") %>

With ActiveRecord you can use:

User.allconditions => ["users.id NOT IN (?)", array])

Sweet, just learning ActiveRecords, but was using .find( :all ... )
I like this!


--
Kind Regards,
Rajinder Yadav

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