dmitchell / ruby_snowflake_client

Gem wrapper to enable ruby to use libsnowflakeclient for faster queries

ruby_snowflake_client

A small gem wrapping libsnowflakeclient whose goal is to stream query results so as to not allocate memory for more than a row at a time.

Build libsnowflakeclient and copy headers and lib files into this project:

UNIVERSAL=false LIB_SNOWFLAKE_DIR=../libsnowflakeclient/ rake build_libsnowflakeclient

where UNIVERSAL is only required on macos to prevent it trying to create the deprecated 32bit binary.

Build this library (requires the above)

rake build

Install this library (there are other means): gem install pkg/ruby_snowflake_client-0.1.0.gem

Usage:

# may raise an IoError if it fails to instantiate or connect
connection = SnowflakeCConnection.new(host, account, 'WH', database, schema, user, password, 'SERVICE_ROLE', timezone_or_nil, port_or_nil)
query = <<~QUERY
  select account_id, order_time, amount 
    from orders where order_time < #{4.hours.ago}
      and shipping_time is null
    order by order_time
QUERY

# read query
status = connection.snowflake_query(query) do |row|
  process_overdue_order(row[0], # account
                        Time.at(row[1]), # order time--all dates and times come back as seconds since epoch
                        row[1])
end
raise status if status  # status either `nil` or sprintf(msg, "%d: %s", error->error_code, error->msg);

# update query (can use for any query where you only care about the number of affected rows)
rows, status = connection.snowflake_update("delete from orders where status = 'cancelled' and order_time < #{1.year.ago}")
if rows
  puts "Deleted #{rows} cancelled orders from over a year ago"
elsif status
  raise status  # error_code: error_msg
end