select on decimal (float) value

Anon

Hi,
I have a trouble with this select:

SELECT id
FROM sizes
WHERE size='$size'
AND product_id='$product_id'

size is defined as FLOAT di 4,1

ie:

SELECT id
FROM sizes
WHERE size='12.4'
AND product_id='$product_id'

My trouble is that there is not difference between 12.4 or 12.1.
The select returns rows also if 12.4 is not present into the table, because there is a 12,1 data.

Can you help me?

[deleted]

12.4 and 12,4 are different notations for the same value.

Why do you want them to be different? (what'sthe point?)

tomhath

I didn't test it, but the quotes around $size don't look right. Try the query without them. You might be comparing integers instead of floats.

Anon

You might be comparing integers instead of floats.

It's right: that is my problem.
ok, thank you.
I will try it on monday.

Anon

Sorry for my mistake, the comma isn't my trouble.

The trouble is that if I do that:

SELECT id from myTable
WHERE size='12.4'
AND product_id='$product_id'

and there is already a 12.3 (or another decimal with 12) in my table,
my select returns a row.

Well, I want an exact SELECT with my float number (12.4). I don't want a select with the rounded integer (12).

How can I do it?

Anon

I don't understand.

size 12.7 is in my table
Now I write:

$preControllo="
SELECT id
FROM sizes
WHERE size='12.7'
;";

//or size=12.7 ... I have the same results
$eseguiQuery=mysql_query($preControllo) or die ("MySql error: ".mysql_error());
$preNum=mysql_numrows($eseguiQuery);

print "<BR><BR>".$preNum."<BR><BR>";

and the query returns 0 rows.

If I have 12.2
12.3
ecc.
in my table

and i do:

$preControllo="
SELECT id
FROM sizes
WHERE size='12'
;";

(or size=12)

The rows number of the result is the number of decimal values in my table.

IE: if I have 12.2, 12.3, 12.4
The query returns 3 rows.

Can you help me, please?

Anon

It has to be either a round-off or extra character. Try something like this (put the ID of the 12.7 row in for the ????).

select id, '>>>' + size + '<<<'
from sizes where id = ????

But it really looks like it's rounding 12.2, 12.3, and 12.4 down to 12 for some reason.

How is the table defined (the type of each column?)