Support empty double-quoted string in SQL object body

[robverschoor]

Description

This fixes the long-standing bug that a reference to a double-quoted empty string, when located in the body of a procedure, function or trigger, raises an error even though QUOTED_IDENTIFIER is OFF. This is due to the PG backend interpreting any double-quoted string as an identifier, whose length cannot be zero. It is fixed by replacing "" by '' at the ANTLR stage.

Signed-off-by: Rob Verschoor [email protected]

Issues Resolved

BABEL-5385 Comparison to empty double-quoted string raises error about 'zero-length delimited identifier'

Test Scenarios Covered

• Use case based - Yes

• Boundary conditions - Yes

• Arbitrary inputs - N/A

• Negative test cases - Yes

• Minor version upgrade tests - N/A

• Major version upgrade tests - N/A

• Performance tests - N/A

• Tooling impact - N/A

• Client tests - N/A

Check List

• Commits are signed per the DCO using --signoff

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[coveralls]

Pull Request Test Coverage Report for Build 11843318267

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Details

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• 265 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.002%) to 74.723%

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Files with Coverage Reduction	New Missed Lines	%
contrib/babelfishpg_tsql/src/tsqlIface.cpp	265	90.3%

Totals
Change from base Build 11831695974:	0.002%
Covered Lines:	45637
Relevant Lines:	61075

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💛 - Coveralls