Sequel::SQL::ComplexExpressionMethods

Adds methods that allow you to treat an object as an instance of a specific ComplexExpression subclass.

Methods

extract(datetime_part)

Extract a datetime part (e.g. year, month) from self:

Sequel[:date].extract(:year) # extract(year FROM "date")

Also has the benefit of returning the result as a NumericExpression instead of a generic ComplexExpression.

    # File lib/sequel/sql.rb
726 def extract(datetime_part)
727   NumericExpression.new(:extract, datetime_part, self)
728 end

sql_boolean()

Return a BooleanExpression representation of self.

    # File lib/sequel/sql.rb
731 def sql_boolean
732   BooleanExpression.new(:NOOP, self)
733 end

sql_number()

Return a NumericExpression representation of self.

~Sequel[:a] # NOT "a"
~(Sequel[:a].sql_number) # ~"a"

    # File lib/sequel/sql.rb
739 def sql_number
740   NumericExpression.new(:NOOP, self)
741 end

sql_string()

Return a StringExpression representation of self.

Sequel[:a] + :b # "a" + "b"
Sequel[:a].sql_string + :b # "a" || "b"

    # File lib/sequel/sql.rb
747 def sql_string
748   StringExpression.new(:NOOP, self)
749 end