[HIVE-9897] Issue a warning when using an existing table/view name as an alias in a with statement.

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.13.1
• Component/s: Hive

Environment

cdh5.3.0

• Assignee: Pengcheng Xiong
• Reporter: Mario Konschake
• Created: 09/Mar/15 14:21
• Updated: 01/Jun/15 18:06
• Resolved: 01/Jun/15 18:06

Description

Consider the following query:

WITH
table_a AS (
    SELECT
        'johndoe' AS name
    FROM
        my_table
)

SELECT
    DISTINCT name
FROM
    table_a;

Observation:

If a table or a view with name `table_a` exists it is used instead of the one defined in the WITH statement.

Expectation:

As the expectation is ambiguous (using the alias in the WITH statement vs. using the existing table) issuing a warning when using a existing name in a WITH statement is recommended.

Issue Links

• is related to: HIVE-10698 query on view results fails with table not found error if view is created with subquery alias (CTE).
• relates to: HIVE-10698 query on view results fails with table not found error if view is created with subquery alias (CTE).