# currently
if ( DB query word exists in table ) {
    DB do update counter
}
else
    DB insert word with counter val of 1
}

# this will always use 2 DB queries per iter, whereas this code.....

unless ( execute(UPDATE table SET counter = counter + 1 WHERE word = ?) ) {
    # this should only fail if the bound word does not exist so 
    # know we know we really needed an INSERT with default value (1)
    # but we have saved 1 DB query - IN A LOOP
    execute(INSERT INTO table VALUES ( word, 1 ) )
}

# will only use one query if it is an update (probably the most common case)
# and still only uses 2 for an insert.
# this can yield savings -> 50% depending on Update:Insert ratio