Re: Can this query go faster???

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Hi,

Is it possible to get this query run faster than it does now, by adding
indexes, changing the query?

SELECT customers.objectid FROM prototype.customers, prototype.addresses
WHERE
customers.contactaddress = addresses.objectid
ORDER BY zipCode asc, housenumber asc
LIMIT 1 OFFSET 283745

Explain:

Limit  (cost=90956.71..90956.71 rows=1 width=55)
  ->  Sort  (cost=90247.34..91169.63 rows=368915 width=55)
        Sort Key: addresses.zipcode, addresses.housenumber
        ->  Hash Join  (cost=14598.44..56135.75 rows=368915 width=55)
              Hash Cond: ("outer".contactaddress = "inner".objectid)
              ->  Seq Scan on customers  (cost=0.00..31392.15
rows=368915 width=80)
              ->  Hash  (cost=13675.15..13675.15 rows=369315 width=55)
                    ->  Seq Scan on addresses  (cost=0.00..13675.15
rows=369315 width=55)

The customers table has an index on contactaddress and objectid.
The addresses table has an index on zipcode+housenumber and objectid.

When the resulting relation contains all the info from both tables, indexes won't help, seq scan is inevitable.


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