My local rails database is mysql but my server host (heroku) is Postgres.
Probably a fairly common combination.
I have an advanced search form that work locally in development mode but not in production and it looks like it might be a Postgres specific thing as the heroku log shows I am getting:
LINE 1: ...,18,19,17,4,32,23,24,16,6,13) and (version_number >= 0.0 or ...
2014-06-23T01:47:54.198026+00:00 app[web.1]: ^
2014-06-23T01:47:54.198022+00:00 app[web.1]: ActiveRecord::StatementInvalid (PG::UndefinedFunction: ERROR: operator does not exist: character varying >= numeric
2014-06-23T01:47:54.198028+00:00 app[web.1]: HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
in the log.
Is there another way to do >= in postgres.
Locally I do see that the datatype is string in schema.rb which is probably the problem. Is there a way I can cast it into integer for rails for pg?
PostgreSQL definitely does have the >= operator: http://www.postgresql.org/docs/current/static/functions-comparison.html
Your problem is that you seem to be comparing a string with a number.
Is there a way I can cast it into integer for rails for pg?
Probably - but we can't see your code. Did you write the SQL? Or did you rely on ActiveRecord? DataMapper? Sequel? Can't help without seeing what you did.
Related
I am using gem rails~> 5.2 and gem mysql2 >= 0.3.13, < 0.5.
I have a model Lawer, which has an array column lawer_filed [sic].
# Model lawer.rb
serialize :lawer_field, Array
Then I created a Lawer, and I can get the lawer_field value as follows:
=> Lawer.first.lawer_field
=> ["2", "3", "5"]
Now, I want to find one Lawer with a query using lawer_field. I tried:
#lawer = Lawer.where("lawer_field && ARRAY[?]", "2")
which raised an error like this:
ActiveRecord::StatementInvalid (Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '['2']) LIMIT 11' at line 1: SELECT `lawers`.* FROM `lawers` WHERE (lawer_field && ARRAY['2']) LIMIT 11)
There is a mistake in my SQL syntax, but I don't how to fix it. Can anyone help?
MySQL, unlike PostgreSQL, does not support arrays in database. Therefore you needed to add this line:
serialize :lawer_field, Array
This means that you have a string field in your database, but whenever ActiveRecord is unpacking results returned by the database, it maps them directly to an instance of Ruby Array. What this means is that your only option to filter the results in the database is with any MySQL string comparison functions, LIKE, etc.
Your options are to either use LIKE or perform some other String functions (which will not perform well as you will be unable to use indices) or build another table, add a has_many association to it and use MySQL the way it was supposed to be used. You could also, of course, migrate to PostgreSQL, but that seems to be the most extreme option.
EDIT: you could also consider using MySQL`s JSON, which has been added recently. That depends on your version of MySQL though.
I didn't try this answer because I don't have any Rails project ready for testing, but I think the problem is in the syntax.
I think it should be something like this:
Lawer.where("lawer_field IN (?)", "2")
I have SQLite and MySQL installed on my local and development machine respectively. Following is working fine on my local machine(with SQLite):
select_single = {'date': "strftime('%%Y-%%m-%%d',projectName_Modelname.created)"}
queryset.extra(select=select_single)
But since strftime doesn't work with MySQL(link), I tried using DATE_FORMAT() as suggested in given link and other places too.
Though now when I execute below:
select_single = {'date': "DATE_FORMAT(projectName_Modelname.created, '%%Y-%%m-%%d')"}
queryset.extra(select=select_single)
Following error comes:
DatabaseError: (1054, "Unknown column 'projectName_Modelname.created' in 'field list'")
where 'created' is Datetime field in Django model 'Modelname' of app 'projectName'
To debug when I replace projectName_Modelname.created with NOW() no error comes. I have also tried just Modelname.created instead of projectName_Modelname.created though with no benefit?
Note: I am using Django1.5.5
I think it should be something like:
date_raw_query = {'date': "date_format(created, '%%Y-%%m-%%d')"}
and then try
queryset.extra(select=date_raw_query)
Hope that works in your setup. I have tried this on Django 1.7 and MySQL and seems to be working.
Also remember that if SQL errors start coming up, you can always do a print queryset.extra(select=date_raw_query).query to see what might be going wrong.
And when it comes to writing compatible code between SQLite and MySQL like this one, writing a custom MySQL function has been suggested here
But I would suggest otherwise. It's better to have a similar dev environment with MySQL setup in local and also, upgrade Django as soon as possible. :P
According to "Ruby datetime suitable for mysql comparison", I should be able to do:
Time.now.to_s(:db)
This doesn't appear to be valid anymore. I get:
irb(main):001:0> Time.now.to_s(:db)
ArgumentError: wrong number of arguments (1 for 0)
from (irb):1:in `to_s'
from (irb):1
from C:/Ruby22/bin/irb:11:in `<main>'
Does this functionality still exist or do I have to manually format the date and time to fit MySQL format?
I'm using ruby 2.2.2.
Time#to_s doesn't accept arguments in Ruby. If you're using Rails, ActiveSupport::TimeWithZone supplies the to_s method you were referring to.
To get this format in Ruby without ActiveSupport you can use:
Time.now.strftime('%Y-%m-%d %H:%M:%S')
I have completed migrating database from sqlserver to mysql but it seems to have problems in rails. When i fetch record in rails console for eg:
<AuthAdmin:0xb6e506f8 #attributes={"Status"=>"1", "LastUpdateSeqNo"=>nil, "CreationDate"=>"2005-08-03 22:53:57", "AuthAdminID"=>"8987", "PropertyID"=>nil, "Password"=>"trustbss", "LastUpdate"=>"2012-07-12 05:15:02", "UserType"=>"0", "LoginName"=>"dev"}
Now attributes such as CreationDate and AuthAdminID suppose to be date and integer are displaying as string.But when I do
AuthAdmin.find(:first).AuthAdminID.class output is Fixnum
You can check record given above,it shows string. Now when i do arithmatic operation in my views caught issue string can't be coerced into Fixnum.Explicitly changing everything to their own TYPE is a very bad idea.
Hope that explain my problem.
Look like no one come across this problem.
I have the following code that run on heroku inside a controller that intermittently fails. It's a no-brainer that it should work to me, but I must be missing something.
#artist = Artist.find(params[:artist_id])
The parameters hash looks like this:
{"utf8"=>"������",
"authenticity_token"=>"XXXXXXXXXXXXXXX",
"password"=>"[FILTERED]",
"commit"=>"Download",
"action"=>"show",
"controller"=>"albums",
"artist_id"=>"62",
"id"=>"157"}
The error I get looks like this:
ActiveRecord::StatementInvalid: Mysql::Error: : SELECT `artists`.* FROM `artists` WHERE `artists`.`id` = ? LIMIT 1
notice the WHEREartists.id= ? part of the statement? It's trying to find an ID of QUESTION MARK. Meaning Rails is not passing in the params[:artist_id] which is obviously in the params hash. I'm at complete loss.
I get the same error on different pages trying to select the record in a similar fashion.
My environment: Cedar Stack on Heroku (this only happens on Heroku), Ruby 1.9.3, Rails 3.2.8, files being hosted on Amazon S3 (though I doubt it matters), using the mysql gem (not mysql2, which doesn't work at all), ClearDB MySQL database.
Here's the full trace.
Any help would be tremendously appreciated.
try sql?
If it's just this one statement, and it's causing production problems, can you omit the query generator just for now? In other words, for very short term, just write the SQL yourself. This will buy you a bit of time.
# All on one line:
Artist.find_by_sql
"SELECT `artists`.* FROM `artists`
WHERE `artists`.`id` = #{params[:artist_id].to_i} LIMIT 1"
ARel/MySQL explain?
Rails can help explain what MySQL is trying to do:
Artist.find(params[:artist_id]).explain
http://weblog.rubyonrails.org/2011/12/6/what-s-new-in-edge-rails-explain/
Perhaps you can discover some kind of difference between the queries that are succeeding vs. failing, such as how the explain uses indexes or optimizations.
mysql2 gem?
Can you try changing from the mysql gem to the mysql2 gem? What failure do you get when you switch to the mysql2 gem?
volatility?
Perhaps there's something else changing the params hash on the fly, so you see it when you print it, but it's changed by the time the query runs?
Try assigning the variable as soon as you receive the params:
artist_id = params[:artist_id]
... whatever code here...
#artist = Artist.find(artist_id)
not the params hash?
You wrote "Meaning Rails is not passing in the params[:artist_id] which is obviously in the params hash." I don't think that's the problem-- I expect that you're seeing this because Rails is using the "?" as a placeholder for a prepared statement.
To find out, run the commands suggested by #Mori and compare them; they should be the same.
Article.find(42).to_sql
Article.find(params[:artist_id]).to_sql
prepared statements?
Could be a prepared statement cache problem, when the query is actually executed.
Here's the code that is failing-- and there's a big fat warning.
begin
stmt.execute(*binds.map { |col, val| type_cast(val, col) })
rescue Mysql::Error => e
# Older versions of MySQL leave the prepared statement in a bad
# place when an error occurs. To support older mysql versions, we
# need to close the statement and delete the statement from the
# cache.
stmt.close
#statements.delete sql
raise e
end
Try configuring your database to turn off prepared statements, to see if that makes a difference.
In your ./config/database.yml file:
production:
adapter: mysql
prepared_statements: false
...
bugs with prepared statements?
There may be a problem with Rails ignoring this setting. If you want to know a lot more about it, see this discussion and bug fix by Jeremey Cole and Aaron: https://github.com/rails/rails/pull/7042
Heroku may ignore the setting. Here's a way you can try overriding Heroku by patching the prepared_statements setup: https://github.com/rails/rails/issues/5297
remove the query cache?
Try removing the ActiveRecord QueryCache to see if that makes a difference:
config.middleware.delete ActiveRecord::QueryCache
http://edgeguides.rubyonrails.org/configuring.html#configuring-middle
try postgres?
If you can try Postgres, that could clear it up too. That may not be a long term solution for you, but it would isolate the problem to MySQL.
The MySQL statement is obviously wrong, but the Ruby code you mentioned would not produce it. Something is wrong here, either you use a different Ruby code (maybe one from a before_filter) or pass a different parameter (like params[:artist_id] = "?"). Looks like you use nested resources, something like Artist has_many :albums. Maybe the #artist variable is not initialized correctly in the previous action, so that params[:artist_id] has not the right value?