ST_Distance Issue

Поиск
Список
Период
Сортировка
От Archana Sachin Ghag
Тема ST_Distance Issue
Дата
Msg-id EECE843AE50D6E4E85BE16173C1E84EB0977079AD3@PUNITPMBX01.ad.infosys.com
обсуждение исходный текст
Ответы Re: ST_Distance Issue  (Robert Haas <robertmhaas@gmail.com>)
Список pgsql-bugs
I am calculating distance from my current location with all available regio=
ns(polygons) in my table.
I am using ST_Distance method for this.
My regions are stored with SRID =3D 900913.

Distance for point in Europe from USA region is coming as 122.78.
How come this possible. These regions are so far.

Here is my query. Can you please suggest me how can I get actual distance i=
n meters here.

SELECT distance
(st_geomfromtext('point(-123.574219125 47.8131546948944 0)', 900913),
st_geomfromtext('LINESTRING(-0.791015625 48.4874864798841,9.4921875 54.5975=
278521139,27.59765625 55.3541353102106,36.38671875 48.3124279040718,22.3242=
1875 40.3465441211801,5.888671875 43.8662180065564,-0.791015625 48.48748647=
98841)', 900913)
)

Query returns 122.785055218779

What is significance of SRID here. Am I missing something?
Which SRID should we use for general purpose.

Thanks,
Archana Ghag
----------------------------------------------------
Technology Architect
Microsoft Technology Center
Infosys Technologies Limited
B1, IT Park 1, Hinjawadi, Pune - 411057
Tel:  2022978913(VOIP) : +91-9850872739 (Mobile)
email: archana_ghag@infosys.com<mailto:archana_ghag@infosys.com>


**************** CAUTION - Disclaimer *****************
This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended solely
for the use of the addressee(s). If you are not the intended recipient, ple=
ase
notify the sender by e-mail and delete the original message. Further, you a=
re not
to copy, disclose, or distribute this e-mail or its contents to any other p=
erson and
any such actions are unlawful. This e-mail may contain viruses. Infosys has=
 taken
every reasonable precaution to minimize this risk, but is not liable for an=
y damage
you may sustain as a result of any virus in this e-mail. You should carry o=
ut your
own virus checks before opening the e-mail or attachment. Infosys reserves =
the
right to monitor and review the content of all messages sent to or from thi=
s e-mail
address. Messages sent to or from this e-mail address may be stored on the
Infosys e-mail system.
***INFOSYS******** End of Disclaimer ********INFOSYS***

В списке pgsql-bugs по дате отправления:

Предыдущее
От: Maxim Boguk
Дата:
Сообщение: Re: BUG #6296: High level backend-write activity on db
Следующее
От: Teun Hoogendoorn
Дата:
Сообщение: Re: BUG #6293: JDBC driver performance