Can you reuse a mysql result set in PHP?

php mysql mysql-select-db
MarathonStudios picture MarathonStudios · Jan 9, 2011 · Viewed 8.7k times · Source

I have a result set I pull from a large database:

$result = mysql_query($sql);

I loop through this recordset once to pull specific bits of data and get averages using while($row = mysql_fetch_array($result)). Later in the page, I want to loop through this same recordset again and output everything - but because I used the recordset earlier, my second loop returns nothing.

I finally hacked around this by looping through a second identical recordset ($result2 = mysql_query($sql);), but I hate to make the same SQL call twice. Any way I can loop through the same dataset multiple times?

Answer

Matthew Flaschen picture Matthew Flaschen · Jan 9, 2011

Use:

mysql_data_seek($result, 0);

You get this "free", since it's already buffered.

As a separate note, you can explicitly do an unbuffered query with mysql_unbuffered_query.

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