SQL: the powerful 1=1

This is a tip I inspired today as I have to make a cursor and needed to use a dynamic where in order to avoid COBOL code.
It is well known to the SQL programmers that using CASE you can make very flexible WHERE's assigning values to a variable field.
But what is you need to assign different values to different variable regarding different conditions. Then you need to use 1=1.  Simple but POWERFUL.

The standard  way case is used in the WHERE clause is
[code]
Select *
  from table1
 where 1=1
    and variable1=
          case
           when condition1 true then value1
          when condition2 true then value2
          else value3
          end
[/code]

I use 1=1 so that it would be easy to comment all ANDs. But if 1=1 is true ann 1=(all numbers except 1) is false then ...

[code]
Select *
  from table1
 where 1=
          case
          when variable1 = condition1 true
            and  variable2 = (select * froom table2
                                         where etc etc
                                              and et etc)
          then 1
          case
          when(variable3 = condition2 true
            and  variable4 = (select * froom table2
                                         where etc etc
                                              and et etc))
              or variable5 <> condition7
          then 1       
          else value0
          end
[/code]

WOW
when 1=1 or 1<>1 builds so powerful dynamic and flexible WHERE clause!!!

http://www.ibmmainframeforum.com/db2/topic12066.html