set hive.mapred.supports.subdirectories=true; set hive.optimize.skewjoin.compiletime = true; CREATE TABLE T1(key STRING, val STRING) SKEWED BY (key, val) ON ((2, 12)) STORED AS TEXTFILE; LOAD DATA LOCAL INPATH '../../data/files/T1.txt' INTO TABLE T1; CREATE TABLE T2(key STRING, val STRING) SKEWED BY (key) ON ((3)) STORED AS TEXTFILE; LOAD DATA LOCAL INPATH '../../data/files/T2.txt' INTO TABLE T2; -- One of the tables is skewed by 2 columns, and the other table is -- skewed by one column. Ths join is performed on the both the columns -- adding a order by at the end to make the results deterministic EXPLAIN SELECT a.*, b.* FROM T1 a JOIN T2 b ON a.key = b.key and a.val = b.val; SELECT a.*, b.* FROM T1 a JOIN T2 b ON a.key = b.key and a.val = b.val ORDER BY a.key, b.key, a.val, b.val;