[PHOENIX-68] Add hint "NO_STAR_JOIN" to indicate if star join optimization should be avoided for multi inner join queries

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.0.0
• Fix Version/s: 3.0.0
• Assignee: Wei Xue
• Reporter: Wei Xue
• Due: 21/Feb/14
• Created: 21/Feb/14 02:50
• Updated: 21/Nov/15 02:16
• Resolved: 22/Feb/14 00:29

Description

We enable a SQL hint called "NO_STAR_JOIN" to allow for choosing different execution plans for multi inner join queries.

For example:
select * from A inner join B on A.ab_id = B.ab_id inner join C on A.ac_id = C.ac_id and B.bc_id = C.bc_id;

When using star-join optimization, the execution steps will be like:
hash B, hash C --> join A

If star-join is turned off, the execution steps will be like:
hash A --> join B --> hash temp result AB --> join C