String query = "A = LOAD 'data1' using "+ DummyCollectableLoader.class.getName() +"() as (id, name, grade);" +
"B = LOAD 'data2' using "+ DummyIndexableLoader.class.getName() +"() as (id, name, grade);" +
"C = join A by id left, B by id using 'merge';" +
"store C into 'out';";
LogicalPlan lp = Util.buildLp(pigServer, query);
LOStore store = (LOStore)lp.getSinks().get(0);
LOJoin join = (LOJoin)lp.getPredecessors(store).get(0);
assertEquals(LOJoin.JOINTYPE.MERGE, join.getJoinType());
PigContext pc = new PigContext(ExecType.MAPREDUCE,cluster.getProperties());
pc.connect();