Exportando tabela MySQL para formato XLS usando PHP

Esta funcionalidade geralmente é usada para exportação de relatórios ou ainda backup em formato CVS ( Excel ). É muito simples a função exporta todos os dados de uma determinada tabela para o formato CSV.

//create query to select as data from your table
$select = "SELECT * FROM table_name";

//run mysql query and then count number of fields
$export = mysql_query ( $select )
or die ( "Sql error : " . mysql_error( ) );
$fields = mysql_num_fields ( $export );

//create csv header row, to contain table headers
//with database field names
for ( $i = 0; $i < $fields; $i++ ) {
$header .= mysql_field_name( $export , $i ) . ",";
}

//this is where most of the work is done.
//Loop through the query results, and create
//a row for each
while( $row = mysql_fetch_row( $export ) ) {
$line = '';
//for each field in the row
foreach( $row as $value ) {
//if null, create blank field
if ( ( !isset( $value ) ) || ( $value == "" ) ){
$value = ",";
}
//else, assign field value to our data
else {
$value = str_replace( '"' , '""' , $value );
$value = '"' . $value . '"' . ",";
}
//add this field value to our row
$line .= $value;
}
//trim whitespace from each row
$data .= trim( $line ) . "\n";
}
//remove all carriage returns from the data
$data = str_replace( "\r" , "" , $data );

//create a file and send to browser for user to download
header("Content-type: application/vnd.ms-excel");
header("Content-disposition: csv" . date("Y-m-d") . ".csv");
header( "Content-disposition: filename=".$file_name.".csv");
print "$header\n$data";
exit;