Class: Select

Inherits:
Expression show all
Defined in:
lib/eno/expressions.rb

Constant Summary collapse

S_SELECT = 
'select %s%s'
S_DISTINCT = 
'distinct '
S_DISTINCT_ON = 
'distinct on (%s) '
S_DISTINCT_ON_SINGLE = 
'distinct on %s '

Constants inherited from Expression

Expression::S_AND, Expression::S_DIV, Expression::S_EQ, Expression::S_GT, Expression::S_GTE, Expression::S_LT, Expression::S_LTE, Expression::S_MINUS, Expression::S_MOD, Expression::S_MUL, Expression::S_NEQ, Expression::S_OR, Expression::S_PLUS, Expression::S_TILDE

Instance Attribute Summary

Attributes inherited from Expression

#members, #props

Instance Method Summary collapse

Methods inherited from Expression

#!=, #!@, #%, #&, #*, #+, #-, #/, #<, #<=, #==, #=~, #>, #>=, #^, #as, #cast, #desc, #in, #initialize, #inner_join, #join, #not_in, #not_null?, #null?, #over, #|

Constructor Details

This class inherits a constructor from Expression

Instance Method Details

#distinct_clause(sql) ⇒ Object 



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# File 'lib/eno/expressions.rb', line 510

def distinct_clause(sql)
  case (on = @props[:distinct])
  when nil
    nil
  when true
    S_DISTINCT
  when Array
    S_DISTINCT_ON % on.map { |e| sql.quote(e) }.join(S_COMMA)
  else
    S_DISTINCT_ON_SINGLE % sql.quote(on)
  end
end

#to_sql(sql) ⇒ Object 



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# File 'lib/eno/expressions.rb', line 504

def to_sql(sql)
  S_SELECT % [
    distinct_clause(sql), @members.map { |e| sql.quote(e) }.join(S_COMMA)
  ]
end