How to use database (SQLite3) values in Ruby - sql

When I want to check if a value from an HTML form equals to a value from the database (which it does) it returns false instead of true.
Do I need more code?
Code:
password = params[:password]
password_db = #db.execute('SELECT password FROM dtbs WHERE username=?', [params[:username]])
puts password #returns llol123
puts password_db #returns llol123
check = (password==password_db)
puts check #returns false

I'm guessing the return type of the password_db is in an array or something? Try getting the type of the values
puts password.class
puts password_db.class
I'm guessing they are different.

Using (password_db[0]==password) returns true.
That's the best way.

Related

Rally custom list query not working on string custom field

I have a custom field being added on user story (HierarchicalRequirement) level.
The WSAPI documentation shows the following details for the field:
c_CustomFieldName
Required false
Type string
Max Length 32,768
Sortable true
Explicit Fetch false
Query Expression Operators contains, !contains, =, !=
When trying to create a report using Custom List to identify user stories where this field is empty, I add (c_CustomFieldName = "") to the query.
And yet, the result shows rows where this field is not empty.
How can that be?
I tried querying on null, but it didn't work.
thx in advance
What you're doing should work- are you getting errors, or just incorrect data? It almost seems like it's ignoring your query altogether.
I tried to repro both with the custom list app and against wsapi directly and the following all worked as expected:
(c_CustomText = "") //empty
(c_CustomText = null) //empty
(c_CustomText != "") //non-empty
(c_CustomText != null) //non-empty
It's possible you're running into some weird data-specific edge case in your data. It may be worth following up with support.

Neo4J create temp variable within Cypher

So my Top-Level problem is I am trying to return whether a MERGE resulted in the creation of a new Node or not.
In order to do this I was thinking I could just create a simple temp boolean setting it to TRUE using ON CREATE
How I imagine it working:
MERGE(: Person {id:'Tom Jones'})
WITH false as temp_bool
ON CREATE set temp_bool = true
RETURN temp_bool
Obviously this does not work.
I am looking for a way to create arbitrary temp values within a Cypher query, and have the ability to return those variables in the end.
Thanks
You can do what you want, here's how (combination of my first answer, with #cybersam's addition). You just do it with a node property you create and then remove, instead of an unbound variable as you've been trying.
MERGE(tom:Person {id:'Tom Jones'})
ON CREATE set tom.temp_bool = true
ON MATCH set tom.temp_bool = false
WITH tom, tom.temp_bool AS result
REMOVE tom.temp_bool
RETURN result;
In simple merging cases like this where maximum one node could be created, a cleaner way to achieve what you are looking for could be checking the result stats. I case of using Bolt API you should check:
results.consume().counters.nodes_created = 1

how to fetch value of a column which has some default value rails mysql

I had a User model, with attributes email, name ...
I wanted to add a column has_agreed with a default value true. So I added that migration and ran it, it shows properly in the database. Now when I fetch the value, #user.has_agreed, it does not return me any value. I have written has_agreed in the attribute accessible (Rails 3.2).
If I manually change the contents of the database by an update command for this particular user to change has_agreed value to false for user with id 1 and then run the same call, #user.has_agreed, it returns false.
I have historical data and I want to add this default column and can not and do not intend to manually update this column through database. How to get the value?
Also, the issue is with only the old users in the user table. For the new users it works fine.
in user.rb
class User
def has_agreed
# use this line code. if has_agreed not equal false
# read_attribute(:has_agreed) || default_velue
if read_attribute(:has_agreed).blank?
## default value
true
else
read_attribute(:has_agreed)
end
end
end

Rails 3 after_save old value

How do you work with the old values of a record being updated?
For instance in the following code block how would I run a query using the previous winner_id field after I determine that it has indeed changed?
if self.winner_id_changed?
old_value = self.changed_attributes
User.find(old_value)
#do stuff with the old winner....
end
An example output of self.changed_attributes would be:
{"winner_id"=>6}
Do I really have to convert this to a string and parse out the value in order to perform a query on it? old_value[:winner_id] doesn't seem to do anything.
Use where instead of find, and the following inject method on changes to generate the desired hash:
if self.winner_id_changed?
old_value = self.changes.inject({}) { |h, (k,v)| h[k] = v.first }
old_user = User.where(old_value)
#do stuff with the old user....
end
You can also use ActiveRecord dirty methods such as:
self.winner_id_was
to get specific attribute's old value. Full documentation may be found here.

ruby on rails store sql result on a variable

Newbie here. I am trying to store the result of my search onto a variable.
#answer = q.answers.select(:name) which runs
"SELECT name FROM "answers" WHERE "answers"."question_id" = 1;" and returns
"t" for true.
It runs fine on the command line and shows the right result. But I want to compare that result to another variable.
How do i extract that result? #answer[0], or #answer, or answer_var = #answer[0]
i.e.
if #answer == some_other_variable OR
if #answer[0] == some_other_variable OR
if answer_var == some_other_variable
what value do #answer[0] and #answer[0] hold and how can I print the value to the log file? not the web page. I know it must be simple, but I can't get my head around it.
Thanks.
It's not really an answer to your question but...
If you want to follow "the rails way", you should better use Models and not deal with SQL at all.
E.g. :
#answer = q.answers.first # answers is an array, take the first
if #answer.name == ...
For the logging, I suggest you that : http://guides.rubyonrails.org/debugging_rails_applications.html#the-logger