Fixed case expression when one of the branch is NUMERIC and other is of EXACT NUMERIC.

[Yvinayak07]

Issues

CASE statement doesn't gives correct typmod when one of the branch is numeric and other is of exact numeric. The precision is being set 5 and scale is set to 4 in babelfish.
So expected result (123.0000) won't fit in Numeric(5,4). So we need to figure out correct precision and scale in this case.

SELECT CASE
WHEN 1 = 0 THEN 0.0001
ELSE 123
END;
Expected Result (TSQL): 123.0000
Actual Result (Babelfish): "Msg 33557097, Level 16, State 1, Line 2
numeric field overflow"
2)

Changes made to fix the issues

In the tsql_select_common_typmod hook, allowed exact numeric types for calculating correct precision and scale.

Task: BABEL-5678
Authored-by: yashneet vinayak [email protected]
Signed-off-by: yashneet vinayak [email protected]

Test Scenarios Covered

• **Use case based -**YES

• **Boundary conditions -**YES

• **Arbitrary inputs -**YES

• **Negative test cases -**YES

• Minor version upgrade tests -

• Major version upgrade tests -

• Performance tests -

• Tooling impact -

• **Client tests -**YES

Check List

• Commits are signed per the DCO using --signoff

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[coveralls]

Pull Request Test Coverage Report for Build 13945425615

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 27 of 27 (100.0%) changed or added relevant lines in 4 files are covered.
• 444 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.04%) to 74.998%

---

Files with Coverage Reduction	New Missed Lines	%
contrib/babelfishpg_tsql/src/pl_handler.c	6	90.37%
contrib/babelfishpg_tsql/src/pltsql_identity.c	13	93.87%
contrib/babelfishpg_tsql/src/dbcmds.c	199	59.29%
contrib/babelfishpg_tsql/src/hooks.c	226	84.01%

Totals
Change from base Build 13917204879:	-0.04%
Covered Lines:	47453
Relevant Lines:	63272

---

💛 - Coveralls

[KushaalShroff]

Can we fix this for UDTs as well?

[Yvinayak07]

For Case and Union we are handling UDT's before this hook.

[KushaalShroff]

Nit: Multi-line