Do not write output files for computed columns when executing dbDoc. Fixes #1088

[rozenshteyn]

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

A clear and concise description of the change being made.

Fix dbDoc fails to generate documents for an Oracle database when an index is created using a filter clause. Fixes #1088.
Skip writing an html file for Oracle database columns which have the computed flag set (i.e. the column was created based on the content of the filter clause of an index).

Things to be aware of

• I constrained the code change to only apply to the Oracle database. I'm not sure if other database types could have the same issue whereupon the column name is set to the content of the index filter clause in the

  liquibase/liquibase-core/src/main/java/liquibase/snapshot/jvm/IndexSnapshotGenerator.java

  Lines 296 to 297 in 9d6d144

  	returnIndex.getColumns().set(position - 1, new Column()
  	.setRelation(returnIndex.getRelation()).setName(definition, true));

• Since I was not sure how to properly mock a static method in groovy/spock, I created DBDocVisitorTest.java.

Things to worry about

• None at this time.

Additional Context

None at this time.

[github-actions]

Unit Test Results

  4 752 files  +12    4 752 suites  +12   31m 33s ⏱️ - 3m 3s
  4 695 tests  - 16    4 459 ✔️  - 19     236 💤 +3  0 ❌ ±0 
55 560 runs  +12  50 252 ✔️ +  7  5 308 💤 +5  0 ❌ ±0 

Results for commit d5c03ff. ± Comparison against base commit fe07fae.

♻️ This comment has been updated with latest results.

[filipelautert]

Hi @rozenshteyn ! Thanks for the PR.
I ran the same test case from the issue on Postgres and had the same problem, so you were right that it's not just an Oracle problem. But I tried a different approach: I used the original class but changed the SnapshotControl to just bring Table and Columns as below (DBDocVisitor line 129), and it worked on Postgres (index wasn't listed as column):

        DatabaseSnapshot snapshot = SnapshotGeneratorFactory.getInstance().createSnapshot(
                database.getDefaultSchema(), database, new SnapshotControl(database, Table.class, Column.class));

Could you help test it on Oracle? So maybe this would be a simpler approach to fix this?

[rozenshteyn]

@filipelautert I tested your proposed fix with the Oracle db. While it does resolve the issue of failing to write out db documentation, it creates a new issue whereupon the index info is missing in the produced db documentation. Since you've mentioned that original issue affects not just the Oracle db, I went ahead and modified my fix by removing the restriction that it applies to the Oracle db only.

[filipelautert]

@rozenshteyn thanks for testing out my approach! So all seems good, moving along. Thanks for the fix.

[filipelautert]

Working fine, also adds tests.

[XDelphiGrl]

This PR addresses a bug in the generation of database documentation where empty HTML files were created for Oracle computed columns.

• New unit tests added to validate fix.
• Automated functional tests passing; https://github.com/liquibase/liquibase-pro-tests/actions/runs/3473764788
• No additional testing required.

APPROVED