Fix (#7002) Where Condition Build Issue

[VarusHsu]

• Do only one thing
• Non breaking API changes
• Tested

What did this pull request do?

Add brackets wrap when sql expression contains ||

User Case Description

• single Expr without brackets wrapped.(follow previous rules)
• multiple Expr and contains || will brackets wrapped.(new feature)

Playground Link

go-gorm/playground#728

Issue Link

#7002

[sprataa]

great find, but, I believe the reason why this is not covered in the first place is because || or && are not part of the ANSI SQL standard.

as an example, || is the concatenate operator in postgresql and && is not supported. in postgresql select 'this' || ' ' || 'is' = 'this is' yields the same result as select ('this' || ' ' || 'is') = 'this is'. logically select 1 = 1 || 2 = 2 yields a syntax error and select (1 = 1)::text || (2 = 2)::text yields the string 'truetrue' as supposed.

while this change you are proposing looks harmless, I don't believe there's any good reason to have these extra comparisons overhead for something which is not a standard for the engines gorm supports.

my 2 cents are, you should be using OR, AND and CONCAT so your SQL code is ANSI compliant and works with every engine.

cheers

[VarusHsu]

My thanks for your answer. @sprataa I found this feature by accident and never read standard SQL docs before.That confused me(a green hand programmer). cheers