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From Jean-Yves Linet <jy.li...@gmail.com>
Subject Re: Float versus Double
Date Tue, 25 Oct 2011 22:48:29 GMT
Hi,
May be you should have read the doc before...
DOUBLE is 8 bytes and REAL is 4 bytes.

FLOAT depends of the precision you specified. Did you set a precision ?

<<The FLOAT data type is an alias for a REAL or DOUBLE PRECISION data type,
depending on the precision you specify.
The default precision for FLOAT is 53 and is equivalent to DOUBLE PRECISION.
A
precision of 23 or less makes FLOAT equivalent to REAL. A precision of 24 or
greater
makes FLOAT equivalent to DOUBLE PRECISION. If you specify a precision of 0,
you
get an error. If you specify a negative precision, you get a syntax error.>>



2011/10/25 anthonyri <anthony.rich@inbox.com>

>
> Hi,
>
> I changed all my doubles to float expecting a smaller database, but the
> size
> was identical.
>
> I thought doubles were 8 bytes and floats only 4 bytes. I have over a
> million records in the database, with several doubles per record. I created
> a completely new database, identical in every respect, except all doubles
> were changed to floats and reimported the data.
>
> Can anyone explain why the database size was exactly the same?
>
> Thanks.
>
> Anthony
> --
> View this message in context:
> http://old.nabble.com/Float-versus-Double-tp32720294p32720294.html
> Sent from the Apache Derby Users mailing list archive at Nabble.com.
>
>


-- 
Jean-Yves LINET

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