ruby/SQLite database interface Post: 302663291

Sponsored Content

Special Forums UNIX and Linux Applications ruby/SQLite database interface Post 302663291 by LMHmedchem on Thursday 28th of June 2012 12:58:28 AM

06-28-2012

Registered User

ruby/SQLite database interface

Hello,

I'm not sure this is quite the right place, but there do seem to be allot of posts with folks using ruby to play nicely with databases so I thought I would give it a go.

I am starting a long process of developing a database application bases on SQLite and ruby. This will run on various linux flavors as well as windows/cygwin. I am using ruby because the interface will eventually be browser based and ruby on rails or Sinatra seems like a good way to get that working. I have looked at some tutorials, but they are either too simple or too complicated. My first step is to do a simple import of a tab delimited text file to create a SQLlite database. There would be one database and several tables, so I need to know how to map each column in the file to table/column. It could be just one table for now if that is simpler.

Can some point me in the right direction to get me going? I have worked through allot of this tutorial,
SQLite Ruby tutorial

This code,

Code:

#!/usr/bin/ruby

require 'sqlite3'

begin
    
    db = SQLite3::Database.open "test.db"
    db.execute "CREATE TABLE IF NOT EXISTS Cars(Id INTEGER PRIMARY KEY, 
        Name TEXT, Price INT)"
    db.execute "INSERT INTO Cars VALUES(1,'Audi',52642)"
    db.execute "INSERT INTO Cars VALUES(2,'Mercedes',57127)"
    db.execute "INSERT INTO Cars VALUES(3,'Skoda',9000)"
    db.execute "INSERT INTO Cars VALUES(4,'Volvo',29000)"
    db.execute "INSERT INTO Cars VALUES(5,'Bentley',350000)"
    db.execute "INSERT INTO Cars VALUES(6,'Citroen',21000)"
    db.execute "INSERT INTO Cars VALUES(7,'Hummer',41400)"
    db.execute "INSERT INTO Cars VALUES(8,'Volkswagen',21600)"
    
rescue SQLite3::Exception => e 
    
    puts "Exception occured"
    puts e
    
ensure
    db.close if db
end

inserts some data to a table, but a hard coded comma separated list is a long way from a delimited text file. I think it's fine for the mapping to be hard coded for now, but this is something that would eventually be entered from a browser interface. At the end of the day, one function would be to select a file from a web interface and load it into a SQLite database. There would be mapping for each column in the file to a table/column in the database, and also a hash to determine if the record already exists. Where a record already exists, data could be added, where it doesn't exist, it will be created.

This is relatively straightforward stuff, but it always seems to take a while to get going.

I can post some sample files if that would help.

Thanks for the advice,

LMHmedchem

LMHmedchem

View Public Profile for LMHmedchem

Find all posts by LMHmedchem

7 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

sqlite issue?

i'm on freebsd 5.2.1, and from a fresh installation i've used pkg_add for the latest ported version of apache, as well as installing php 5. supposedly php5 comes with native support for sqlite (in the binary package), and this is what i added. i am trying to install a site engine (the 'gyrator'...

2. HP-UX

sqlite database in HP-UX vs Linux

Hi everybody, We have a cgi application which accesses sqlite database. It works fine in Linux environment but the same code doesn't enter data into the database when done in HP-UX environment. Should the codes vary depending on whether it is Linux or HP-UX. Regards Ruma

3. Shell Programming and Scripting

hell and sqlite

Hi everyone, I have a requirement that requires me to fill an sqlite database with 100,000 entries (no duplicates). I will start out by giving the command that will insert the values necessary to populate the database: # sqlite /var/local/database/dblist "insert into list...

4. SCO

Change SCO - GUI or Desktop interface to DOS based interface

Hi all I have installed a demo version of SCO OpenServer 5.0.2, I finally found it is Desktop Interface, I would like to know how to change its interface to dos based interface? If you have any ideas, please tell me then. Thank you

5. Shell Programming and Scripting

Several processes writing to an SQLite database at the same time

I have several bash scripts that write to an SQLite3 database at the same time. At some occasion the database returns: SQL error: database is locked. How would be the best way, to make a process to wait until the data base is 'free' again. I tried: sqlite3 test.db ".timeout 1000; update....."...

6. Web Development

Web Interface for a database

Hi Gents, What is the best way to create a web interface for mysql database? That I can manage my data for root user and for normal user as well according to their privileges? Assuming that I use Linux as a server and Apache as a web server and my database is mysql. Thanks in advance

7. AIX

Need a graphical interface on AIX server to create database

Hello, Please suggest me the ways how to get graphical interface on AIX server.I need to create oracle database for which I need graphical access. Best regards, Vishal

LEARN ABOUT DEBIAN

dh-make-ruby

DH-MAKE-RUBY(1) 														   DH-MAKE-RUBY(1)

NAME

       dh-make-ruby - build Debian source package from Ruby library

USAGE

       dh-make-ruby [OPTIONS] TARBALL|DIRECTORY

DESCRIPTION

       dh-make-ruby will create a basic Debian source package from a tarball named TARBALL generated with gem2tgz, or from a DIRECTORY containing
       Ruby code and metadata in a .gemspec file.

OPTIONS

       -p PACKAGE, --package PACKAGE
	   Uses PACKAGE as package name. By default, new packages will be named as ruby-$gem, where $gem is the upstream name. If the package is
	   mainly used as a library, then it should use the default. On the other hand, if the packages is mainly used as an application, then you
	   should drop the ruby- prefix by using this option an explicit package u.

       --ruby-versions VERSIONS
	   Ruby versions to build the package for. This is used to generate the X-Ruby-Versions: field in the source package, that can later be
	   used to tune this value.  By default, gem2deb generates a package that works on all known Ruby versions, but it might be necessary to
	   only build the package for Ruby 1.8, for example (using --ruby-versions "ruby1.8").

       -h, --help
	   Displays the help

       -v, --version
	   Displays version information and exits.

SEE ALSO

       gem2deb(1), dh_ruby(1)

COPYRIGHT AND AUTHORS

       Copyright (c) 2011, Lucas Nussbaum <lucas@debian.org>

       This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
       the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.

								    2012-03-06							   DH-MAKE-RUBY(1)