[SR-Users] How to correctly check if the variable is set?

[Alex Balashov]

On 01/14/2013 09:16 AM, Mino Haluz wrote:

> and how to check null value taken from database?
>
> $dbr(ra=>[0,0]) == ?

That depends on what you truly mean by "null" value.  :-)

If you want to check for no rows returned, you can check the value of 
$dbr(ra=>rows) to get a count, e.g.

    if($dbr(ra=>rows) < 1)

    if(! $dbr(ra=>rows))

If you are looking to test for a truly NULL value as opposed to an empty 
string, I suspect that varies with database API.  I use db_postgres, and 
if I remember correctly, 'defined' works for that:

    if(! defined $dbr(ra=>[0,0]))

That's IIRC.  I am not 100.0% sure.

However, other DB interface implementations may return an empty string 
even in case of a null value, in which case strempty() may be the better 
test.

-- Alex

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Alex Balashov - Principal
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