Re: Help with join syntax sought - Mailing list pgsql-general

This seems to be working.  I had to take a different approach as I
had misapprehended GROUP BY completely.


SELECT *
FROM currency_exchange_rates AS xchg1
WHERE id
  IN (
    SELECT id
    FROM currency_exchange_rates as xchg2
    WHERE
         xchg1.currency_code_base = xchg2.currency_code_base
         AND
         xchg1.currency_code_quote = xchg2.currency_code_quote
    ORDER BY currency_code_base,
             currency_code_quote,
             effective_from DESC
    LIMIT 1 )
ORDER BY currency_code_base,
         currency_code_quote,
         effective_from DESC

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James B. Byrne                mailto:ByrneJB@Harte-Lyne.ca
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