Fix dependency query for PostgreSQL 15

[Domm98CZ]

Impact

• Bug fix (non-breaking change which fixes expected existing functionality)
• Enhancement/New feature (adds functionality without impacting existing logic)
• Breaking change (fix or feature that would cause existing functionality to change)

Description

Invalid datytype caused sql error and then 0 changes detected.
Hoewer command return success code.

Additional Context

Error in console with --log-level=DEBUG

[2022-11-09 13:28:32] FINE [liquibase.executor] Executing with the 'jdbc' executor
[2022-11-09 13:28:32] FINE [liquibase.diff] Cannot get object dependencies: Error executing SQL WITH RECURSIVE preference AS (
    SELECT 10 AS max_depth  -- The deeper the recursion goes, the slower it performs.
         , 16384 AS min_oid -- user objects only
         , '^(londiste|pgq|pg_toast)'::text AS schema_exclusion
         , '^pg_(conversion|language|ts_(dict|template))'::text AS class_exclusion
         , '{"SCHEMA":"00", "TABLE":"01", "CONSTRAINT":"02", "DEFAULT":"03",
      "INDEX":"05", "SEQUENCE":"06", "TRIGGER":"07", "FUNCTION":"08",
      "VIEW":"10", "MVIEW":"11", "FOREIGN":"12"}'::json AS type_ranks),
               dependency_pair AS (
                   WITH relation_object AS ( SELECT oid, oid::regclass::text AS object_name  FROM pg_class )
                   SELECT DISTINCT                          substring(pg_identify_object(classid, objid, 0)::text, E'(\\w+?)\\.') as referenced_schema_name,                          CASE classid
                              WHEN 'pg_constraint'::regclass THEN (SELECT CONTYPE FROM pg_constraint WHERE oid = objid)
                              ELSE objid::text
                              END AS CONTYPE,
                         CASE classid
                              WHEN 'pg_attrdef'::regclass THEN (SELECT attname FROM pg_attrdef d JOIN pg_attribute c ON (c.attrelid,c.attnum)=(d.adrelid,d.adnum) WHERE d.oid = objid)
                              WHEN 'pg_cast'::regclass THEN (SELECT concat(castsource::regtype::text, ' AS ', casttarget::regtype::text,' WITH ', castfunc::regprocedure::text) FROM pg_cast WHERE oid = objid)
                              WHEN 'pg_class'::regclass THEN rel.object_name
                              WHEN 'pg_constraint'::regclass THEN (SELECT conname FROM pg_constraint WHERE oid = objid)
                              WHEN 'pg_extension'::regclass THEN (SELECT extname FROM pg_extension WHERE oid = objid)
                              WHEN 'pg_namespace'::regclass THEN (SELECT nspname FROM pg_namespace WHERE oid = objid)
                              WHEN 'pg_opclass'::regclass THEN (SELECT opcname FROM pg_opclass WHERE oid = objid)
                              WHEN 'pg_operator'::regclass THEN (SELECT oprname FROM pg_operator WHERE oid = objid)
                              WHEN 'pg_opfamily'::regclass THEN (SELECT opfname FROM pg_opfamily WHERE oid = objid)
                              WHEN 'pg_proc'::regclass THEN objid::regprocedure::text
                              WHEN 'pg_rewrite'::regclass THEN (SELECT ev_class::regclass::text FROM pg_rewrite WHERE oid = objid)
                              WHEN 'pg_trigger'::regclass THEN (SELECT tgname FROM pg_trigger WHERE oid = objid)
                              WHEN 'pg_type'::regclass THEN objid::regtype::text
                              ELSE objid::text
                              END AS REFERENCED_NAME,
                          substring(pg_identify_object(refclassid, refobjid, 0)::text, E'(\\w+?)\\.') as referencing_schema_name,                           CASE refclassid
                              WHEN 'pg_namespace'::regclass THEN (SELECT nspname FROM pg_namespace WHERE oid = refobjid)
                              WHEN 'pg_class'::regclass THEN rrel.object_name
                              WHEN 'pg_opfamily'::regclass THEN (SELECT opfname FROM pg_opfamily WHERE oid = refobjid)
                              WHEN 'pg_proc'::regclass THEN refobjid::regprocedure::text
                              WHEN 'pg_type'::regclass THEN refobjid::regtype::text
                              ELSE refobjid::text
                              END AS REFERENCING_NAME
                   FROM pg_depend dep
                            LEFT JOIN relation_object rel ON rel.oid = dep.objid
                            LEFT JOIN relation_object rrel ON rrel.oid = dep.refobjid, preference
                   WHERE deptype = ANY('{n,a}')
                     AND objid >= preference.min_oid
                     AND (refobjid >= preference.min_oid OR refobjid = 2200) -- need public schema as root node
                     AND classid::regclass::text !~ preference.class_exclusion
                     AND refclassid::regclass::text !~ preference.class_exclusion
                     AND COALESCE(SUBSTRING(objid::regclass::text, E'^(\\\\w+)\\\\.'),'') !~ preference.schema_exclusion
                     AND COALESCE(SUBSTRING(refobjid::regclass::text, E'^(\\\\w+)\\\\.'),'') !~ preference.schema_exclusion
                   GROUP BY classid, objid, refclassid, refobjid, deptype, rel.object_name, rrel.object_name
               )
 select referenced_schema_name,
    (CASE
      WHEN position('.' in referenced_name) >0 THEN substring(referenced_name from position('.' in referenced_name)+1 for length(referenced_name))
      ELSE referenced_name
    END)  AS referenced_name,
   referencing_schema_name,
   (CASE
      WHEN position('.' in referencing_name) >0 THEN substring(referencing_name from position('.' in referencing_name)+1 for length(referencing_name))
      ELSE referencing_name
    END)  AS referencing_name from dependency_pair where REFERENCED_NAME != REFERENCING_NAME  AND ( REFERENCED_NAME like 'public.%' OR REFERENCED_NAME NOT LIKE '%.%')
 AND (CONTYPE::text != 'p' AND CONTYPE::text != 'f')
 AND referencing_schema_name is not null and referencing_name is not null: ERROR: CASE types text and "char" cannot be matched
  Position: 939
[2022-11-09 13:28:32] INFO [liquibase.diff] changeSets count: 0
[2022-11-09 13:28:32] INFO [liquibase.diff] No changesets to add.
Liquibase command 'diff-changelog' was executed successfully.

Unchanged sql runned directly on database:

Changed sql runned directly on database:

Thanks.

[nvoxland]

Pre-Review Notes

Change makes sense, improves the postgresql query to handle the datatype in an internal query better

Questions I have:

• None

Potential risks:

• It should work on older postgresql versions, automated tests will tell us for sure

What could make the full review difficult:

• Nothing

[github-actions]

Unit Test Results

  4 752 files  ±0    4 752 suites  ±0   33m 4s ⏱️ - 4m 39s
  4 721 tests ±0    4 488 ✔️ ±0     233 💤 ±0  0 ❌ ±0 
55 668 runs  ±0  50 340 ✔️ ±0  5 328 💤 ±0  0 ❌ ±0 

Results for commit b342432. ± Comparison against base commit 344f471.

♻️ This comment has been updated with latest results.

[filipelautert]

Tests passed. Besides that I ran the changed SQL on Postgresql 9.6 and 12 and it worked fine.

[XDelphiGrl]

This PR fixes a datatype mismatch between text and char when querying pg_constraint.contype, which returns a char. Liquibase was inconsitently casting pg_constraint.contype to text, resulting in the error. This is fixed.

• Fix is specific to Postgres.
• Automated functional and test harness executions passing.
• No additional testing required.

APPROVED