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