Re: Query precision issue

Hello Sairam,

What is the type of the colum?, what version of postgres are you using?

I didn't had any problem retrieving data in both ways... check out the below
=============================================

test=# create temp table test (col1 float);
CREATE TABLE
test=# insert into test values(-107.689878);
INSERT 0 1
test=# select * from test where col1=-107.6898780000;
col1
-------------
-107.689878
(1 row)

test=# select * from test where col1=-107.689878000;
col1
-------------
-107.689878
(1 row)

test=# select * from version();

version
------------------------------------------------------------------------------------------------------------------
PostgreSQL 8.4.1 on x86_64-redhat-linux-gnu, compiled by GCC gcc (GCC)
4.1.2 20071124 (Red Hat 4.1.2-42), 64-bit
(1 row)

============================================

Thanks
Deepak

On Mon, Oct 25, 2010 at 10:11 AM, Sairam Krishnamurthy
<kmsram420(at)gmail(dot)com>wrote:

> All,
>
> I have simple query like 'select * from table1 where
> column1=-107.6898780000'. This returns an empty set. But there is data
> corresponding to this value of column.
>
> When I looked more into it, it seems like a precision issue. The value for
> column1 is -107.689878.
>
> More interesting is that the following query fetches the row,
>
> 'select * from table1 where column1=-107.689878000'
>
> Note that there are only three trailing zeros in the second query while
> there were four in the first.
>
> Can somebody help me to find out the problem? I can very well truncate the
> trailing zeros when querying, but I am interested in finding why an
> additional trailing zero returns an empty set.
>
> --
> Thanks,
> Sairam Krishnamurthy
> +1 612 859 8161
>
>