[HIVE-18416] Initial support for TABLE function

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.0
• Fix Version/s: 3.0.0
• Component/s: Parser
• Labels: TODOC3.0
• Target Version/s: 3.0.0
• Assignee: Jesus Camacho Rodriguez
• Reporter: Jesus Camacho Rodriguez
• Created: 09/Jan/18 21:33
• Updated: 22/May/18 23:13
• Resolved: 13/Jan/18 02:14

Description

Include support for TABLE function derived table. In SQL standard, it is defined as:

<table function derived table> ::=
  TABLE <left paren> <collection value expression> <right paren>

Further, include limited support for its usage as LATERAL derived table.

This will allow Hive to execute queries such as:

SELECT tf.col1, tf.col2, tf.col3
FROM
  TABLE(VALUES('A', 10, 30.0),('B', 20, 30.0)) AS tf(col1, col2, col3);
SELECT tf.col1, tf.col2, tf.col3
FROM
  (SELECT key, value FROM src) t,
  LATERAL TABLE(VALUES('A', 10, t.key),('B', 20, t.key)) AS tf(col1, col2, col3);

The idea is to rely on AST rewriting for such cases, as TABLE can be implemented using inline UDTF with an array of structs representing the rows in the VALUES clause.

Issue Links

• blocks: HIVE-18450 Support TABLE function in CBO
• is related to: HIVE-18451 Support UDTF Operator in SimpleFetchOptimizer
• links to: RB link