while function

[ddtpmyra]

I have two queries in two diffrent tables my question is 'can i add two queries inside my while loop? How to do that?'

while ($row = mysql_fetch_array ($result))

[dlite922]

no, a while loop only takes one argument.

What you can do is have two separate while loops, or have a nested while loop.

You can query the DB with an inner while loop, inner query if you need a piece of data from your outer loop, outer query.

However I *strongly* disagree with this. It is very resource intensive and proves the structure of your database is poor (see Database Normalization).






Dan

[Atli]

I would have to agree with Dan.
This sounds like you need to rethink your queries rather than restructure your code.

Maybe we could be a bit more specific if you showed us the queries you are using.

@dlite922
Technically not true.

A while loop doesn't take any arguments. It does execute a statement on every loop, however.
This statement can do whatever you want it to, for example:

$result1 = mysql_query("SELECT * FROM someTable");
$result2 = mysql_query("SELECT * FROM someOtherTable");
 
while(
  ($row1 = mysql_fetch_assoc($result1)) or 
  ($row2 = mysql_fetch_assoc($result2))
) {
  echo "From someTable:\n";
  foreach($row1 as $_key => $_value) {
    echo " - $_key = $_value\n";
  }
  echo "From someOtherTable:\n";
  foreach($row2 as $_key => $_value) {
    echo " - $_key = $_value\n";
  }
}
 

This would run through two result objects, printing ever row of each one.
I wouldn't recommend using this tho, as there are much better alternatives.
Just pointing out the possibility :)

You can even execute simple programs within that statement, without adding anything to the actual code block.
For example:

<?php
while(
    (($i++ or true) // Always adds 1 to $i and evaluates true
    and print(" Row $i" . PHP_EOL)) // Prints a line.
    and ($i < 10) // Breaks the loop once $i reaches 10
)
{
  // An empty code block! :D
}
?>
 

This would loop from 1 to 10, printing a line to the output for every loop.
Again, not exactly something you would want to use in a real program, but you get the point.