similar to: understanding rails transactions support.

I''m trying to create a sequence with no gaps in my db (contrived example, but should work out the same as my real one), and believe db-managed transactions are the way to go about this. It''s my first real ''go'' at transactions, so I may be mistaken about how things really work. Anyway.. Consider this example code: Class Invoice < ActiveRecord::Base def

So there are a couple parts to this question. I am trying to implement the rpart/random forest algorithms on a transaction lists. That is to say i am trying to train models in order to deduce what are the most predictive transactions within a customers history in order apply this model to future test data and identify accounting irregularities(ie. this account had x and y so they should have also

Hi Torvald, On Oct 27, 2010, at 8:01, Torvald Riegel wrote: > On Tuesday 26 October 2010 14:33:02 Duncan Sands wrote: >>> transaction properties (eg, virtually atomic + isolated execution) for >>> ordinary program code. Thus, to make incrementing a counter thread-safe, >>> you could say __transaction { counter++; } and the compiler would >>> transform this

Hi, I have a transaction in which a duplicate key exception is being thrown by MySQL. I assume this happens when I try to do a save. The problem is that before the save, I do a destroy on another object as part of the transaction. Catching the exception by doing this, User.transaction do begin objA.destroy objB.save <-- causing exception rescue Exception => exc

On Tuesday 26 October 2010 14:33:02 Duncan Sands wrote: > > transaction properties (eg, virtually atomic + isolated execution) for > > ordinary program code. Thus, to make incrementing a counter thread-safe, > > you could say __transaction { counter++; } and the compiler would > > transform this code so that it uses a TM library, which in turn does > > concurrency

Hi Torvald, > I would like to know whether the community is interested in getting support > for Transactional Memory (TM) merged in upstream LLVM. I guess not :( TM basically gives you > transaction properties (eg, virtually atomic + isolated execution) for > ordinary program code. Thus, to make incrementing a counter thread-safe, you > could say __transaction { counter++; } and

Hi, I would like to know whether the community is interested in getting support for Transactional Memory (TM) merged in upstream LLVM. TM basically gives you transaction properties (eg, virtually atomic + isolated execution) for ordinary program code. Thus, to make incrementing a counter thread-safe, you could say __transaction { counter++; } and the compiler would transform this code so

Hi, I'm doing a Market Basket Analysis in which I have a list of transaction id's in column 2 and transactions(product names) in column 1. I read this into a transaction file using a txn<-read.transaction(file="data.csv",format='single', rm.duplicates=F, cols=c(1,2)) If I want to use the apriori algorithm everything seems to be running fine. However it is when I want

Hey, I just updated from the edge and it looks like this _issue_ has resurfaced. Yesterday things were working (stories and specs). No code base changes, only rspec and rspec_on_rails After updating today I now need to set <config.txn...fixtures> to false in the spec_helper.rb to get the specs running, the stories are fine. Looks like the fixture loading is trying to start a txn. I

Hi fellow programmers, I was looking for how to keep integrity in some financial transactions and I saw this "This could even happen if you use transactions with the ‘serializable’ isolation level." in the uniqueness page http://api.rubyonrails.org/classes/ActiveRecord/Validations/ClassMethods.html#method-i-validates_uniqueness_of. How this is possible with the serializablo

Hello! According to ActiveRecord transactions documentation, User.transaction do User.create(:username => ''Kotori'') User.transaction(:requires_new => true) do User.create(:username => ''Nemu'') raise ActiveRecord::Rollback end end User.find(:all) # => Returns only Kotori But I get both records in database (tested on

Hello, I have rails using a MSSQL db. The set up works fine with low volume, but with 2+ requests/second I keep on getting the following error: DBI::DatabaseError: Execute OLE error code:80004005 in Microsoft OLE DB Provider for SQL Server Cannot create new connection because in manual or distributed transaction mode. HRESULT error code:0x80020009 Exception occurred.: SELECT

Waay back at the end of 3.0.3 dev cycle I brought up the issue of XenD running far too many xenstore transactions per-request http://lists.xensource.com/archives/html/xen-devel/2006-10/msg00487.html Short summary: # nc -U /var/lib/xend/xend-socket GET /xend/domain/test Resulted in approx 16 xenstore transactions for a domain with one disk and one NIC - this increases as # of devices

Hello, I have the following structure: model foo has_many :bars:, :dependent => true end model bar belongs_to :foo end In my action, when i try to save foo: def save begin f = foo.new f.a = 5 begin b = bar.new b.a = 10 f.bars << b rescue Exception => exc ... end f.save! <-- This does not happen

Hi, I have 2 models, how can I save both of them in one transaction? I want to do something like this: begin transaction project.save person.save end transaction The only examples I''ve seen is with saving 2 instances of the same model in a transaction. thanks scott. -------------- next part -------------- An HTML attachment was scrubbed... URL:

FIXED: Transaction is a reserved word, and it cannot be used even though I put it into its own module. So my guess is Transactions::Transaction still somehow got resolved to the Rails internal Transaction class. Renamed the Transaction (and its subclasses) to Transact and it works fine now. Thanks! -- cmdjohnson On Sat, Jun 9, 2012 at 3:08 AM, Commander Johnson

Hi all.. I was going to submit this as a bug...but thought I should learn more first ... When #save is called on an ActiveRecord a transaction is started to catch any potential problems and try and recover from them. This is cool. But.. as a result of the Transaction module being mixed in quite late in the game, the transactions system is one of the *first* things to get initiated.........is

I cant seem to find much information apart from the basics on transactions in rails. I have 5 nested transactions, and am performing the following basic operations: @whatever1.transaction do @whatever2.transaction do .... @whatever2.something = "foo" @whatever1.something = "bar" @whatever1.save @whatever2.save ..... end end ((( I had tried using

Hello! I experienced problems with testing transactions which are supposed to be rolled back, but are not, because of transactional fixtures eliminating the inner transaction. Can this be worked around somehow without turning off transactional fixtures? Maybe savepoints can help this? Does anyone have any experience with savepoints to achieve nested transaction functionality? Both Postgres

hi, i have problem with transactions and multiple databases. Object1 and Object2 are two different models/databases with different connections, when i use only one model: Object1.transaction do object1.value1 = "123456" object1.save do_some_error end it''s ok, error is produced, nothing is commited and database is unchanged. when i use 2 models, described at