[IMPALA-4918] Support getting column comments via HS2

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 2.5.0
• Fix Version/s: Impala 2.11.0
• Component/s: Catalog
• Labels: newbie
• Assignee: Csaba Ringhofer
• Reporter: Davy Xu
• Created: 13/Feb/17 11:14
• Updated: 24/Oct/17 15:19
• Resolved: 24/Oct/17 15:19

Description

I create table including column comment in impala-shell as following:
create table test(a int comment 'dddd');

Then I use jdbc class DatabaseMetaData to get column name and comment as following:
Class.forName("org.apache.hive.jdbc.HiveDriver");
Connection conn = DriverManager.getConnection("jdbc:hive2://10.43.183.142:21050/default;auth=noSasl", "impala", "impala");
DatabaseMetaData dbmd = conn.getMetaData();
ResultSet rs = dbmd.getColumns(null, null, "test", null);
while (rs.next())

{ String name = rs.getString("COLUMN_NAME"); int type = rs.getType(); String remarks = Strings.nullToEmpty(rs.getString("REMARKS")); System.out.print("name:" + name + " remarks:" + remarks + " \n"); }

I get column correctly but get comment null.
I use DatabaseMetaData to get column name and comment from table hive. It work correctly,I can get both of them.

So, can't get column comment in query to Impala table is a bug need to be fixed.