Drop all observations with negative values

Hi, I have been trying to delete all negative values from my dataset (instead of doing it by variable) using the below 2 approaches, but am ending up with 0 observations in each case.

APPROACH1

foreach v of var * {
drop if `v' < 0
}

APPROACH 2
egen rmin=rowmin(_all)
drop if rmin<0


Thanks in advance!