Problem in ExecEvalExpr function

Hi,

I have some doubts related to ExecEvalExpr functions which is used to 
executing the expression.

Here we are finding the subexpression recursively.
But I am not able to find it out that where exactly the comparison taking 
place.
For eg.
relation A
id   name   age
relation B
name age status

if query is
select id , name , age , status from A , B where A.name = B.name and A.age 
= B.age.

Then parser find this "and" condition and divide this into two expression.
But I am not getting in which function exactly these comparison between 
tupleslot taking place.

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| Sandeep Satpal |
| M.Tech Student |
| Lab 212 KReSIT |
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