Execution of CASE statement in SQL query -


let's have table named 'neighbors' contains variable 'name', , selecting name , using case statement assign values second variable, 'age'. syntax 1 can use case statement in sql takes 2 different forms:

1) simple case expression: 

    case name            when 'george' 36            when 'alfred' 40         else null        end age

2) searched case expression:

    case           when name = 'george' 36            when name = 'alfred' 40         else null         end age

the 2 statements doing same thing. question is, how these statements handled in memory? handled same, or may 1 more efficient other?

https://docs.microsoft.com/en-us/sql/t-sql/language-elements/case-transact-sql

correct syntax either

case name        when 'george' 36        when 'alfred' 40     else null    end  age

or

case      when name = 'george' 36        when name = 'alfred' 40     else null    end  age

the benefit of latter allows multiple columns evaluated:

case      when name = 'george' , othercolumn = 'stuff' 36        when 'alfred' 40     else null    end  age

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