Parsing a CSV File to a Rails Database

Posted by Schroedinger on Stack Overflow See other posts from Stack Overflow or by Schroedinger
Published on 2010-04-19T04:14:53Z Indexed on 2010/04/19 4:23 UTC
Read the original article Hit count: 254

Filed under:

ruby

|

csv

|

ruby-on-rails

|

parsing

G'day guys,

I'm using fasterCSV and a rake script to parse a csv with about 30 columns into my rails db for a 'Trade' item. The script works fine when all of the values are set to strings, but when I change it to a decimal, int or other value, everything goes to hell.

Wondering if fasterCSV has built in int etc parsing or whether I'll have to manage these within my model.

Basically, I'm given a giant amount of trades data, need to import it, and then need to provide feedback with say the average trade volume, the times, etc. I understand I can do that all with the wonderful records provided to me by activeRecord but wondered if there was an easier way to populate a rather large Database with a given CSV?

Several of the fields don't have values for certain rows, fasterCSV seems to work perfectly when they're all strings, but not when I try to get decimal or other.

© Stack Overflow or respective owner

Related posts about ruby

Setting up Rails to work with sqlserver

as seen on Stack Overflow - Search for 'Stack Overflow'
Ok I followed the steps for setting up ruby and rails on my Vista machine and I am having a problem connecting to the database. Contents of database.yml development: adapter: sqlserver database: APPS_SETUP Host: WindowsVT06\SQLEXPRESS Username: se Password: paswd Run rake db:migrate… >>> More
marshal data too short!!!

as seen on Stack Overflow - Search for 'Stack Overflow'
My application requires to keep large data objects in session. There are like 3-4 data objects each created by parsing a csv containing 150 X 20 cells having strings of 3-4 characters. My application shows this error- "marshal data too short". I tried this- Deleting the old session table. Deleting… >>> More
Sinatra and XML POST request

as seen on Stack Overflow - Search for 'Stack Overflow'
I don't know is it my mistake or no. So i have that code: <code> post '/singin/get_token' do content_type :xml puts request.body.read puts xmlRequest xmlRequest = REXML::Document.new(request.body.read) ... </code> And when i post something like that: <code> <?xml… >>> More
how to change ruby path from /usr/bin/ruby to /usr/local/bin/ruby

as seen on Stack Overflow - Search for 'Stack Overflow'
reading around the various ruby install tutorials it's required to change path from /usr/bin/ruby to /usr/local/bin/ruby but i cant seem to be able to do it. Ultimately i want to install Ruby 1.9.2, should i uninstall 1.8.7 or what? i tried to install Ruby 1.9.2 with macports, the installation seemed… >>> More
strange bundler error: tar_input.rb:49:in `initialize': not in gzip format (Zlib::GzipFile::Error) o

as seen on Stack Overflow - Search for 'Stack Overflow'
i am getting a strange bundler error when running bundle pack with bundler 0.9.12 any ideas? (see pastie for a better formatted code: http://pastie.org/881328 ) /opt/ruby-enterprise-1.8.7-2010.01/lib/ruby/site_ruby/1.8/rubygems/package/tar_input.rb:49:in `initialize': not in gzip format (Zlib::GzipFile::Error) … >>> More

Related posts about csv

DBD::CSV: How can I generate different behavior with the two f_ext-options ".csv" and ".csv/r"?

as seen on Stack Overflow - Search for 'Stack Overflow'
This is from the DBD::File-documentation: f_ext This attribute is used for setting the file extension where (CSV) files are opened. There are several possibilities. DBI:CSV:f_dir=data;f_ext=.csv In this case, DBD::File will open only table.csv if both table.csv and table exist… >>> More
SUPER CSV write bean to CSV.

as seen on Stack Overflow - Search for 'Stack Overflow'
Here is my class, public class FreebasePeopleResults { public String intendedSearch; public String weight; public Double heightMeters; public Integer age; public String type; public String parents; public String profession; public String alias; public String children; public String siblings; public… >>> More
export to csv using fastercsv and CSV::Writer (Ruby on Rails)

as seen on Stack Overflow - Search for 'Stack Overflow'
What am I trying to do: export data to csv. I have a form which allows user to select the format (from a drop down menu). So based on the selection of the format the ouput is displayed using a ajax call. Works fine for html but when I select the format as csv I don't see any pop up on the screen… >>> More
How can i make changes to this file Encoding?

as seen on Super User - Search for 'Super User'
I have these 3 files 21/08/2014 07:15 PM 122 Tw2AWK.csv 21/08/2014 07:15 PM 125 Tw2Notepad.csv 21/08/2014 07:15 PM 119 Tw2REPL.csv C:\myfilesfile Tw2AWK.csv TwREPL.csv Tw2Notepad.csv Tw2AWK.csv; UTF-8 Unicode text, with CRLF line terminators Tw2REPL… >>> More
Unix sort keys cause performance problems

as seen on Super User - Search for 'Super User'
My data: It's a 71 MB file with 1.5 million rows. It has 6 fields All six fields combine to form a unique key - so that's what I need to sort on. Sort statement: sort -t ',' -k1,1 -k2,2 -k3,3 -k4,4 -k5,5 -k6,6 -o output.csv input.csv The problem: If I sort without keys, it takes 30 seconds… >>> More