crystal-db
Common db api for crystal. You will need to a specific driver to access a database.
Installation
Add this to your application's shard.yml
:
dependencies:
db:
github: crystal-lang/crystal-db
Usage
Since this is an abstract db api, it's usage is through a concrete database driver.
require "db"
require "sqlite3"
DB.open "sqlite3:./file.db" do |db|
db.exec "create table contacts (name string, age integer)"
db.exec "insert into contacts values (?, ?)", "John Doe", 30
args = [] of DB::Any
args << "Sarah"
args << 33
db.exec "insert into contacts values (?, ?)", args
puts "max age:"
puts db.scalar "select max(age) from contacts" # => 33
puts "contacts:"
db.query "select name, age from contacts order by age desc" do |rs|
puts "#{rs.column_name(0)} (#{rs.column_name(1)})"
# => name (age)
rs.each do
puts "#{rs.read(String)} (#{rs.read(Int32)})"
# => Sarah (33)
# => John Doe (30)
end
end
end
Roadmap
Issues not yet addressed
- [ ] Support non prepared statements.
- [ ] Time data type.
- [x] Data type extensibility. Allow each driver to extend the data types allowed.
- [ ] Transactions.
- [ ] Connection pool.
- [ ] Direct access to
IO
to avoid memory allocation for blobs.
Contributing
- Fork it ( https://github.com/crystal-lang/crystal-db/fork )
- Create your feature branch (git checkout -b my-new-feature)
- Commit your changes (git commit -am 'Add some feature')
- Push to the branch (git push origin my-new-feature)
- Create a new Pull Request
Contributors
- bcardiff Brian J. Cardiff - creator, maintainer