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Question

Here is a snippet of code.

for ($g =0; $g++<$idg;) { $ch = mysql_query("SELECT chips FROM reit WHERE id_games='$g' AND id_users='1' ",$db); while ($chg = mysql_fetch_array($ch)) { $chg = $chg['chips']; echo "<td>$chg </td>"; } }

When it is executed, it displays a column of chips (323, 5454, 45345, 43234) , but, let's say, to do id_games and id_users where there are no chips , it will output the same, only without a column, where there was no data. And how to make it so that when he sees that there is nothing, he changed nothing to 0 in the $chg variable? If you disassemble the cycle, it turns out like this:

 select chips from reit where id_users = '1' and id_games = '1'; 43432 select chips from reit where id_users = '1' and id_games = '2'; пусто select chips from reit where id_users = '1' and id_games = '3'; 434234 select chips from reit where id_users = '1' and id_games = '2'; 987

But he will print 43432 434234 987. At the same time, the entire table collapses. Tried to make conditions, but it doesn't work.

 if ($chg == '') { $chg = '0'; }

KiTE KiTE 7,780 15 27 · Answer 1 · 2012-04-13T13:07:26

 select IFNULL(chips, 0) AS chips from reit

Answer 2 · 2012-04-13T12:23:36

Try for the case if the chips have an empty value:

 $chg = $chg['chips']?$chg['chips']:0;

or in request:

 SELECT if(chips,chips,0) as chips FROM reit WHERE id_games='$g' AND id_users='1'

upd: if zero sampling then, as @alexlz correctly comments

 SELECT coalesce(chip, 0) FROM reit WHERE id_games='$g' AND id_users='1'

If 0 - nothing is found, then ... php.net/manual/ru/function.mysql-num-rows.php And coalesce is unlikely to help here.
That would be if the string was, and the value of chips for it was NULL - tads oh.

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