logo       
Google Custom Search
    AddThis Social Bookmark Button
-->

Re: getting julian number from date in libpq: msg#00005

Subject: Re: getting julian number from date in libpq
Thanks for both your quick responses. Hm. If we could alter the SQL automatically, we would; we're trying to keep dates as dates between PostgreSQL and R without changing the query: this means the date subtraction operator or EXTRACT don't really work for us. We're trying to hack into RdbiPgSQL (the connector for R -> postgresql, so that it returns dates to R as dates, not as text). Our queries take twice as long to process because once we get a resultset back with dates, we have to cast all the dates from text to R's date class.

If we could somehow use functions within libpq to massage the query results back so that we could get date as a julian number, that would do it. Or if we could have a custom DATESTYLE. The problem with PQexecParams is that you have to choose binary results for all columns; for most other columns, text is sufficient.

Any other ideas?

On Sep 8, 2005, at 3:45 PM, Tom Lane wrote:
Something involving EXTRACT(EPOCH FROM timestamp) will probably solve
your problem.


On Sep 8, 2005, at 3:37 PM, Michael Fuhr wrote:

In 7.4 and later you could use PQexecParams() to request binary
results; in earlier versions you could use a binary cursor.  But
the result will be days since 1 Jan 2000, not 1 Jan 1970, so you'd
have to do a conversion; you'd also have to convert the binary value
from network byte order to host byte order.  It might be easier to
use the date subtraction operator:


######################################################################
This e-mail is confidential and should not be redistributed or
forwarded by the recipient.  The information contained in this e-mail
message is intended only for the use of the individual or entity named
above.  If the reader of this message is not the intended recipient or
you have received this communication in error, please immediately
notify us by telephone.  Receipt by anyone other than the intended
recipient is not a waiver of any work-product or, if applicable,
attorney-client privilege.

This e-mail does not constitute an offering of any security.  Such an
offering may only be made by means of a private placement memorandum
or other disclosure document.  Nothing in this e-mail constitutes
investment advice.  Past performance is not indicative of future
results.  All e-mail to and from Millburn Ridgefield Corporation and
its affiliates is monitored, stored and made available to regulators
if requested.
######################################################################

---------------------------(end of broadcast)---------------------------
TIP 5: don't forget to increase your free space map settings



<Prev in Thread] Current Thread [Next in Thread>