Class: Linkage::Functions::Length

Inherits:
Linkage::Function show all
Defined in:
lib/linkage/functions/length.rb

Overview

Returns the number of characters in a string.

Constant Summary

Constants inherited from Data

Data::TYPE_CONVERSION_TREE

Instance Attribute Summary

Attributes inherited from Linkage::Function

#args

Attributes inherited from Data

#dataset, #name

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Linkage::Function

#==, [], #collation, #dataset, #dataset=, #initialize, #name, register, #static?

Methods inherited from Data

#collation, #database_type, #initialize, #merge, #static?

Constructor Details

This class inherits a constructor from Linkage::Function

Class Method Details

.function_name ⇒ Object 



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# File 'lib/linkage/functions/length.rb', line 5

def self.function_name
  "length"
end

.parameters ⇒ Object 



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# File 'lib/linkage/functions/length.rb', line 9

def self.parameters
  [[String]]
end

Instance Method Details

#ruby_type ⇒ Object 



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# File 'lib/linkage/functions/length.rb', line 13

def ruby_type
  {:type => Fixnum}
end

#to_expr(options = {}) ⇒ Object 



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# File 'lib/linkage/functions/length.rb', line 17

def to_expr(options = {})
  expr =
    case dataset.database_type
    when :mysql, :postgres
      :char_length.sql_function(@values[0])
    else
      :length.sql_function(@values[0])
    end
end