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Re: fastes way to retrieve segmented without using loop - Mailing list pgsql-general

From Melvin Davidson
Subject Re: fastes way to retrieve segmented without using loop
Date
Msg-id CANu8FiyRkBAwtMGj-=YUc4uJEmMyo0HvrWO9bqVUHr4Er7GKXQ@mail.gmail.com
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In response to fastes way to retrieve segmented without using loop  (Tom Smith <tomsmith1989sk@gmail.com>)
Responses Re: fastes way to retrieve segmented without using loop
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Well, I would say the following might work:

SELECT  *
  FROM table
WHERE  t >=1
LIMIT  99998;

On Sun, Aug 23, 2015 at 5:05 PM, Tom Smith <tomsmith1989sk@gmail.com> wrote:
Hello:

I have a time series table,
using below sql, loop (psque code), I can get one row for each hour

for( H=1: H< 99999; H++){
   select  * from table where  t >= H and t < H+1   limit 1
}

t (time column) is indexed).

Is there a better way to use a issue a SINGLE SQL
with  an array of time start/end pair
so it will be executed once to send back result, which would be much faster
than issuing sql again and again (even with prepared statement and using sql function).

Thanks in Advance



--
Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.

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