Mysqldump with empty result in gzip?

[acicuoulupt]

When I output my MySQL Dump Regularly, it outputs a 30MB File. When I use gzip, 0KB.Here is my code:\[code\]$command = "<path to>mysqldump --opt -h $dbhost -u$dbuser -p$dbpass $dbname | gzip> test.sql.gz";system($command);Result: test.sql.gz 0 KB---------------------------$command = "<path to>mysqldump --opt -h $dbhost -u$dbuser -p$dbpass $dbname > test.sql";system($command);Result: test.sql 30 MB\[/code\]