sbdb/README.md

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Dependencies
============
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You need first the [Bdb](http://github.com/ruby-bdb/bdb) and of course [ruby](http://ruby-lang.org).
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Download
========
via git:
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git clone git://github.com/ruby-bdb/sbdb
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Install
=======
gem build sbdb.gemspec
gem install sbdb-*.gem
Usage
=====
First, open environment and database
require 'sbdb'
Dir.mkdir 'newenv' rescue Errno::EEXIST
env = SBDB::Env.new 'newenv', SBDB::CREATE | SBDB::Env::INIT_TRANSACTION
db = env.btree 'newdb.db', :flags => SBDB::CREATE
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It works nearly like a Ruby-Hash:
db['key'] = 'value'
db['key'] # => 'value'
db.to_hash # => {'key'=>'value'}
db.map {|k, v| "k => v" } # => ["key => value"]
db.count # => 1
db.each {|k,v| puts "#{k}: #{v}" }
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`SBDB::DB#each` uses a `SBDB::Cursor`:
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cursor = db.cursor
cursor.each {|k,v| puts "#{k}: #{v}" }
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**Don't forget to close everything, you've opened!**
cursor.close
db.close
env.close
But you can use a *lambda* to ensure to close everything:
SBDB::Env.new( 'newenv', SBDB::CREATE | SBDB::Env::INIT_TRANSACTION) do |env|
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env.open SBDB::Btree, 'newdb.db', :flags => SBDB::CREATE do |db|
db.to_hash
end
end
`SBDB::DB#to_hash` creates a cursor and close it later.
Tip:
Signal.trap 'EXIT', env.method( :close)