Hi,

I need an ANTI-JOIN (not exists SELECT something from table.../ left join table 
WHERE table.id IS NULL) on the same table. Acutally I have an index to serve 
the not exists question, but the query planner chooses to to a bitmap heap scan.

The table has 100 Mio rows, so doing a heap scan is messed up...

It would be really fast if Postgres could compare the to indicies. Does 
Postgres have to visit the table for this ANTI-JOIN?

I know the table has to be visitied at some point to serve the MVCC, but why so 
early? Can NOT ESISTS only be fixed by the table, because it could miss 
soemthing otherwise?

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