RE: tune between query/join

<SNIP>

>> If you rewrite the condition as the equivalent
>>
>> where a.lowest_amount <= b.amount
>> and a.highest_amount >= b.amount

<SNIP>

>> Create an index on (lowest_amount, highest_amount) and it will fly.

The OP said that this was the query:

>> >> select a.account_number, a.id, b.*
>> >> from account a, tmp_account b
>> >> where b.amount between a.lowest_amount and a.highest_amount

Plus:

>> >> account has 8000000 rows and tmp_account 150000,

And:

>> >> this query takes around 5 hours to run.

So, *assuming* that there is a "missing" semi-colon above, surely this query is returning a selection of rows from an 8,000,00 * 150,000 cartesian product?

With a join between a.<some_id> and b.<some_id>, in addition to the above, it should fly even more?

Mind you, I'm only on my first coffee of the morning and I'm really really not as good an SQL guru as you are, so be gentle with me!

Cheers,
Norm.

Norman Dunbar
Contract Senior Oracle DBA
Capgemini Database Build Team
Internal : 7 28 2051
External : 0113 231 2051

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