Thanks imad,

> It looks like you need a customized version of AExpr Node.
> In the backend parser, an AExpr Node is constructed against each given
> WHERE expression. You can store the weight along with the expression.
> Further, don't forget to upgrade the copy functions and equal
> functions for AExpr if you want to take this weight value all the way
> upto the executor.

I have already done that, alas, it doesn't suffice: During parse analysis 
transformExpr() turns the AExpr into other types, e.g. an OpExpr in case of foo 
= 42.

These newly created OpExprs won't last until they reach the executor in every 
case, though: They are sometimes recreated anew during planning 'manually', 
i.e. not by using the standard copy functions but by creating a new OpExpr node 
and copying the fields on an as-seen-before basis - these are the places where 
my weight gets lost.

To be honest, I consider not using a special copy function a minor design flaw 
:) *sigh*

Anyway, thanks again. But giving a weight to AExpr is just the tip of the 
iceberg when it comes to my final goal - let my weights enter the executor ;)


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