Fix the issue of preserving case of column names in SELECT corrname.colname and Fix the issue of preserving case of column names in SELECT corrname.colname.

[riyajain39]

Description

This pull request fix preserving the original case spelling of column names while selecting named column with a correlation name. It also fix the crash is pre_transform_target_entry for queries that involves DELETE ... OUTPUT with JOIN statement.

Issue 1:
When selecting named column with a correlation name, the lowercase spelling is always returned. The case of column name is not preserved. For instance, select ABC from table, here ABC is the column name. In this case column name becomes downcased. To address this issue, I've made some code modifications to ensure that the column name is handled correctly, whether it's truncated or its case needs to be preserved.

Issue 2:
For the delete queries with join statement, somehow the res->location is not processed correctly. This causes server to crash as the value of last_dot pointer has never been computed. I implemented a check which first computed whether the res->location is correct or not and then further proceed with the code.

Issues Resolved

BABEL-4279
BABEL-4484

Signed-off-by: Riya Jain [email protected]

Test Scenarios Covered

• Use case based - Added test case from original bug.

• Boundary conditions -

• Arbitrary inputs -

• Negative test cases -

• Minor version upgrade tests -

• Major version upgrade tests -

• Performance tests -

• Tooling impact -

• Client tests -

Check List

• Commits are signed per the DCO using --signoff

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