Class: DoubleEntry::Line

Inherits:
ActiveRecord::Base
  • Object
show all
Extended by:
EncapsulateAsMoney
Defined in:
lib/double_entry/line.rb

Overview

This is the table to end all tables!

Every financial transaction gets two entries in here: one for the source account, and one for the destination account. Normal double-entry accounting principles are followed.

This is a log table, and should (ideally) never be updated.

Indexes

The indexes on this table are carefully chosen, as it's both big and heavily loaded.

lines_scope_account_id_idx

ADD INDEX `lines_scope_account_id_idx` (scope, account, id)

This is the important one. It's used primarily for querying the current balance of an account. eg:

SELECT * FROM `lines` WHERE scope = ? AND account = ? ORDER BY id DESC LIMIT 1

lines_scope_account_created_at_idx

ADD INDEX `lines_scope_account_created_at_idx` (scope, account, created_at)

Used for querying historic balances:

SELECT * FROM `lines` WHERE scope = ? AND account = ? AND created_at < ? ORDER BY id DESC LIMIT 1

And for reporting on account changes over a time period:

SELECT SUM(amount) FROM `lines` WHERE scope = ? AND account = ? AND created_at BETWEEN ? AND ?

lines_account_created_at_idx and lines_account_code_created_at_idx

ADD INDEX `lines_account_created_at_idx` (account, created_at);
ADD INDEX `lines_account_code_created_at_idx` (account, code, created_at);

These two are used for generating reports, which need to sum things by account, or account and code, over a particular period.

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.find_id_and_created_at(options) ⇒ Object

Query out just the id and created_at fields for lines, without instantiating any ActiveRecord objects.



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# File 'lib/double_entry/line.rb', line 117

def self.find_id_and_created_at(options)
  connection.select_rows <<-SQL
    SELECT id, created_at FROM #{Line.quoted_table_name} #{options[:joins]}
     WHERE #{sanitize_sql_for_conditions(options[:conditions])}
  SQL
end

Instance Method Details

#account ⇒ Object 



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# File 'lib/double_entry/line.rb', line 81

def 
  DoubleEntry.(self[:account].to_sym, :scope => scope)
end

#account=(account) ⇒ Object 



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# File 'lib/double_entry/line.rb', line 75

def account=()
  self[:account] = .identifier.to_s
  self.scope = .scope_identity
  
end

#code ⇒ Object 



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# File 'lib/double_entry/line.rb', line 71

def code
  self[:code].try(:to_sym)
end

#code=(code) ⇒ Object 



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# File 'lib/double_entry/line.rb', line 66

def code=(code)
  self[:code] = code.try(:to_s)
  code
end

#decrease? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/double_entry/line.rb', line 107

def decrease?
  amount < Money.empty
end

#increase? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/double_entry/line.rb', line 111

def increase?
  amount > Money.empty
end

#pair ⇒ Object 



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# File 'lib/double_entry/line.rb', line 99

def pair
  if decrease?
    [self, partner]
  else
    [partner, self]
  end
end

#partner ⇒ Object 



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# File 'lib/double_entry/line.rb', line 95

def partner
  self.class.find(partner_id)
end

#partner_account ⇒ Object 



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# File 'lib/double_entry/line.rb', line 91

def 
  DoubleEntry.(self[:partner_account].to_sym, :scope => partner_scope)
end

#partner_account=(partner_account) ⇒ Object 



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# File 'lib/double_entry/line.rb', line 85

def partner_account=()
  self[:partner_account] = .identifier.to_s
  self.partner_scope = .scope_identity
  
end