while/foreach/for get 3 results at a time?
I am trying to get 3 results out of a mysql database at a time (so it would display 3 at a time)
So it would be something like
$sql = mysql_query("SELECT * FROM table");
while ($row = mysql_fetch_array($sql)) {
print $row['username'];
print $row['username2'];
print $row['username3'];
}
but $row['username']; and $row['username2']; $row['username3']; would just be the first second and third results out of the mysql table.
and then it would repeat and $row['username']; and $row['username2']; and $row['username3']; would be the 4th, 5th and 6th and so on.
Any idea of how I could do this?
You could do this:
function mysql_fetch_n_rows($rs, $n)
{
$rows = array();
while ($n-- && ($row = mysql_fetch_array($rs)))
{
$rows[] = $row;
}
return $rows;
}
$rs = mysql_query("SELECT * FROM table");
while ($rows = mysql_fetch_n_rows($rs, 3))
{
print $rows[0]['username'];
print $rows[1]['username'];
print $rows[2]['username'];
}
(Disclaimer: obviously you'd need to verify that you actually got 3 rows back. You might only get one or two.)
But I doubt you really need the above code. Generally it's much easier to do a ($i % 3) as some of the other answers suggest. I definitely do not post this answer because I think it's the best general solution, but only as an example of creating a general purpose function instead of trying to hard code this type of solution within the while loop.
You can use limit clauses,
select * from table limit 1, 3
then for the next 3,
select * from table limit 4, 3
(you might want to look up the syntax, I may have the order backwards)
To show just the three results, you can do like this:
$sql = mysql_query("SELECT * FROM table");
$count = 0;
while ($row = mysql_fetch_array($sql)) {
$count++;
if ($count === 3) break;
print $row['username'];
}
Or if you want, you can specify the LIMIT clause in your query to fetch just three records:
$sql = mysql_query("SELECT * FROM table LIMIT 3");
while ($row = mysql_fetch_array($sql)) {
print $row['username'];
}
With LIMIT clause, you can also specify the start index and number of rows to be returned like this:
$sql = mysql_query("SELECT * FROM table LIMIT 4, 3");
The above query will return 3 rows starting from 4th row.
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