babelfish_extensions [DO NOT MERGE] Added wrapper for UPPER() and LOWER() functions for CHAR and NCHAR to handle padding for shorter strings

[DO NOT MERGE] Added wrapper for UPPER() and LOWER() functions for CHAR and NCHAR to handle padding for shorter strings

Open Anikait143 opened this issue 1 year ago • 1 comments

Description

1. Issues

UPPER() and LOWER() functions for CHAR or NCHAR types compared to a string shorter than definition cause condition to fail.
String functions do not handle chinese characters for NVARCHAR type when collation is not used in UPPER() and LOWER() functions

2. Changes made to fix the issues

Added wrapper function handling for UPPER() and LOWER() functions to handle CHAR and NCHAR as VARCHAR and NVARCHAR respectively.

# Input
DECLARE @class NCHAR(2) = N'H'
SELECT '[' + @class + ']' WHERE upper(@class) = N'H'
SELECT '[' + @class + ']' WHERE lower(@class) = N'h'

# previous output (wrong output)               
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

(0 rows affected)

# current output (correct output)
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
[H ]                                                                                                                                                                                                                                                            

(1 rows affected)

# previous output (wrong output)
1> declare @string1 nvarchar(30) = N'比尔·拉';
2> select UPPER(@string1)
3> GO
@string1                      
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
??·?

# current output (correct output)
1> declare @string1 nvarchar(30) = N'比尔·拉';
2> select UPPER(@string1)
3> GO
@string1                      
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
比尔·拉

Added Test Cases for these issues

Task: BABEL- 3395 Authored-by: Anikait Agrawal [email protected] Signed-off-by: Anikait Agrawal [email protected]

Test Scenarios Covered

Use case based - BABEL-3395-vu-*
Boundary conditions -
Arbitrary inputs -
Negative test cases -
Minor version upgrade tests -
Major version upgrade tests -
Performance tests -
Tooling impact -
Memory tests -
Client tests -

Check List

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