(SELECT a * 1 , b FROM TABLE_1) UNION ALL (SELECT a *1 , b FROM TABLE_2);
In this query , attribute number of the VARs are 141 and 2 respectively !! What is the reason for this ??
I am trying to implement a FDW , so i need attribute numbers to fetch the respective columns from my data store . Due to this change in attribute numbers in the case of UNION ALL , this query doesn't provide the necessary output .
But in the plan its given as 1 and 2 respectively . So is there a mapping which PG maintains to convert from 141 to the original attribute number ??