[TRAFODION-1915] support adding/retrieving comments to SQL objects

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Duplicate
• Fix Version/s: 2.3
• Assignee: liu ming
• Reporter: liu ming
• Created: 01/Apr/16 13:05
• Updated: 13/Jan/18 15:53
• Resolved: 13/Jan/18 15:53

Description

It is desired to have compatible capability of Oracle's syntax to add/get comments to SQL objects, like tables and columns, etc.

QiFan give a very good initial design for this:
1. add a new type for column TEXT_TYPE in meta-table TRAFODION."MD".TEXT, say COMMENT_TYPE;
2. allow COMMENT ON syntax in the parser;
3. convert the content of COMMENT ON stmt into insertion/update of a row(s) in the TEXT meta-data table for the SQL object in question;
4. write a UDF to show the comment easily for a SQL object, by hiding the join of the meta-data TEXT and OBJECTS table.

Can be done increamentally since there are a lot of SQL objects. And multiple changes to different components.