[IMPALA-198] Support COMMENT clause for CREATE TABLE ... LIKE

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Impala 0.7
• Fix Version/s: Impala 0.7
• Assignee: Lenni Kuff
• Reporter: John Russell
• Created: 05/Apr/13 21:59
• Updated: 20/Dec/15 00:05
• Resolved: 09/Apr/13 07:06

Description

Please consider supporting the CREATE TABLE ... LIKE usage:

CREATE TABLE t2 LIKE t1 COMMENT 'Reason for creating this new table.'

Could be good for usability if many new / empty tables are created and
nobody knows what they were for.

Functionality-wise, seems like an easy enhancement.

If someone is doing trial and error currently with the CREATE TABLE LIKE syntax,
they can hit a confusing error where it seems like the parser sees the LIKE and
decides it must be in the middle of a query, expecting keywords that normally occur
in the WHERE clause:

[localhost:21000] > create table d2 like t1 comment 'foo';
ERROR: com.cloudera.impala.common.AnalysisException: Syntax error at:
create table d2 like t1 comment 'foo'
^
Encountered: COMMENT
Expected: AS, FULL, GROUP, HAVING, INNER, JOIN, LEFT, LIKE, LIMIT, LOCATION, ON, ORDER, RIGHT, SELECT, UNION, USING, WHERE, PARTITION, COMMA, IDENTIFIER