Critical Description
CREATE TABLE sales (name STRING, id INT)
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';
CREATE TABLE things (id INT, name STRING)
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t';
The 'sales' table has data in a file: sales.txt, and the data is：
Joe 2
Hank 2
The 'things' table has data int two files: things.txt and things2.txt：
The content of things.txt is :
2 Tie
The content of things2.txt is :
2 Tie
SELECT * FROM sales LEFT SEMI JOIN things ON (sales.id = things.id);
will output：
Joe 2
Joe 2
Hank 2
Hank 2
so the result is wrong.
In CommonJoinOperator left semi join should use " genObject(null, 0, new IntermediateObject(new ArrayList[numAliases], 0), true); " to generate data.
but now it uses " genUniqueJoinObject(0, 0); " to generate data.
This patch will solve this problem.