U0100088: GaussDB does not support hierarchical queries

Description

Oracle supports hierarchical queries but GaussDB Distributed does not.

Database Type and Version

• Source database type and version: Oracle versions supported by UGO
• Target database type and version: GaussDB V2.0-8.1 and earlier

Syntax Example

SELECT MAX(stru_grade)   FROM ctp_branch  START WITH id = 0 CONNECT BY PRIOR parent_id = id;

Suggestion

Modify Support for hierarchical query. Select Convert hierarchical queries.

Execute the following statement:

 WITH RECURSIVE dsc_hircl_q AS
(SELECT parent_id,
 stru_grade
FROM ctp_branch
WHERE id = 0
UNION ALL
SELECT dsc_ta1.parent_id,
 dsc_ta1.stru_grade 
FROM dsc_hircl_q
INNER JOIN ctp_branch dsc_ta1
ON dsc_hircl_q.parent_id = dsc_ta1.id)
SELECT MAX(stru_grade)   FROM dsc_hircl_q  ;