Class: Relationize::BqRelationizer

Inherits:
Relationizer show all
Defined in:
lib/relationize/bq_relationizer.rb

Constant Summary collapse

BQ_TS_FMT = 
"%Y-%m-%d %H:%M:%S %:z"
DEFAULT_TYPES = 
{
  Integer    => :integer,
  Fixnum     => :integer,
  Bignum     => :integer,
  BigDecimal => :integer,
  Float      => :float,
  String     => :string,
  TrueClass  => :boolean,
  FalseClass => :boolean,
  Date       => :string,
  Time       => :timestamp
}
CAST = 
{
  "INTEGER"   => -> (val, col) { "INTEGER(#{to_text_literal(val)}) AS #{col}"},
  "FLOAT"     => -> (val, col) { "FLOAT(#{to_text_literal(val)}) AS #{col}" },
  "BOOLEAN"   => -> (val, col) { "BOOLEAN(#{val.nil? ? 'NULL' : (val ? 1 : 0)}) AS #{col}" },
  "STRING"    => -> (val, col) { "STRING(#{to_text_literal(val)}) AS #{col}"},
  "TIMESTAMP" => -> (val, col) { "TIMESTAMP(#{to_timestamp_string(val)}) AS #{col}"}
}

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Relationizer

#initialize

Constructor Details

This class inherits a constructor from Relationize::Relationizer

Class Method Details

.to_text_literal(obj) ⇒ Object 



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# File 'lib/relationize/bq_relationizer.rb', line 22

def self.to_text_literal(obj)
  obj.nil? ? 'NULL' : obj.to_s.gsub(/'/, "\\'").tap { |s| break "'#{s}'" }
end

.to_timestamp_string(obj) ⇒ Object 



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# File 'lib/relationize/bq_relationizer.rb', line 26

def self.to_timestamp_string(obj)
  to_text_literal(obj.is_a?(Time) ? obj.strftime(BQ_TS_FMT) : obj)
end

Instance Method Details

#to_row(val, col), type) ⇒ Object 



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# File 'lib/relationize/bq_relationizer.rb', line 45

def to_row(((val, col), type))
  CAST[type][val, col]
end

#to_s ⇒ Object 



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# File 'lib/relationize/bq_relationizer.rb', line 38

def to_s
  rows = @tuples.map { |tuple|
    "(SELECT #{tuple.zip(@columns).zip(oriented_types).map(&method(:to_row)).join(', ')})"
  }.join(', ')
  "SELECT * FROM (SELECT * FROM #{rows}) AS #{@name}"
end