Methods
Public Class
Public Instance
Attributes
| conditions | [R] |
An array of all two pairs with the first element specifying the condition and the second element specifying the result if the condition matches. |
| default | [R] |
The default value if no conditions match. |
| expression | [R] |
An optional expression to test the conditions against |
Public Class methods
new(conditions, default, expression=(no_expression=true; nil))
Create an object with the given conditions and default value, and optional expression. An expression can be provided to test each condition against, instead of having all conditions represent their own boolean expression.
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# File lib/sequel/sql.rb 1213 def initialize(conditions, default, expression=(no_expression=true; nil)) 1214 raise(Sequel::Error, 'CaseExpression conditions must be a hash or array of all two pairs') unless Sequel.condition_specifier?(conditions) 1215 @conditions = conditions.to_a.dup.freeze 1216 @default = default 1217 @expression = expression 1218 @no_expression = no_expression 1219 freeze 1220 end
Public Instance methods
expression?()
Whether to use an expression for this CASE expression.
[show source]
# File lib/sequel/sql.rb 1223 def expression? 1224 !@no_expression 1225 end
with_merged_expression()
Merge the CASE expression into the conditions, useful for databases that don’t support CASE expressions.
[show source]
# File lib/sequel/sql.rb 1229 def with_merged_expression 1230 if expression? 1231 e = expression 1232 CaseExpression.new(conditions.map{|c, r| [::Sequel::SQL::BooleanExpression.new(:'=', e, c), r]}, default) 1233 else 1234 self 1235 end 1236 end