PIG How do I combine 2 files based one not equal condition - apache-pig

Question

I am trying to find the player that played on the most teams in one year. I have one file wit the the schema of PlayerID, yearID, teamID. I brought the file in twice to try to join where the PlayerID and yearID are equal but the teamID is not. How do I do in in PIG? Can I do a <> in a join statement? Do I need to group them and them compare? I know sql i could join based on the PlayerID and yearID being equal and the teamID not being equal but not sure how to do that in PIG.
I tried this but it is no the right syntax"
batters = LOAD 'hdfs:/user/maria_dev/pigtest/Batting.csv' USING PigStorage(',') AS
(id:chararray,yearid:int, teamid:chararray);
batters1 = LOAD 'hdfs:/user/maria_dev/pigtest/Batting.csv' USING PigStorage(',') AS ` (id:chararray,yearid:int, teamid:chararray);
batter_fltr = FILTER batters BY (yearid > 0) AND (teamid> ' ');
batter1_fltr = FILTER batters1 BY (yearid>0) AND (teamid> ' ');
multi_playr = JOIN batter_fltr BY (yearid,id), batter1_fltr BY(yearid,id) ,LEFT OUTER BY(teamid);

Answer 1

You wanted to find the player that played on the most teams in one year. Therefore, you should group by player & year, then you can count the number of teams per player per year. Finally, order the data by the count descending - the first result will be your answer. There's no need to load the data twice or do a join.
batters = LOAD 'hdfs:/user/maria_dev/pigtest/Batting.csv' USING PigStorage(',') AS
(id:chararray, yearid:int, teamid:chararray);
-- Apply filtering as needed here
teams_per_year = FOREACH (GROUP batters BY (id, yearid))
GENERATE
group.id AS id,
group.yearid AS yearid,
COUNT(batters.teamid) AS num_teams;
ordered_results = ORDER teams_per_year BY num_teams DESC;
DUMP ordered_results;
If you need the distinct number of teams, add a nested DISTINCT:
teams_per_year = FOREACH (GROUP batters BY (id, yearid)) {
dist_teams = DISTINCT batters.teamid;
GENERATE
group.id AS id,
group.yearid AS yearid,
COUNT(dist_teams) AS num_teams;
}