feat: add Unqualified method to return columns without table alias/pr…

[atzedus]

Add Unqualified() method to generated column structures

Summary

This PR adds a new Unqualified() method to generated column structures that returns columns without table alias/prefix. This is useful when you need to reference column names without table qualification, for example in INSERT ... ON CONFLICT clauses or when building dynamic queries.

Changes

• Added Unqualified() method to generated *Columns structures
• Modified buildXColumns() function to conditionally call WithParent() only when tableName is not empty
• Renamed parameter from alias to tableName for better clarity

Example

Before this change, columns were always qualified with table name:

Orders.Columns.ID  // generates: "orders"."id"

Now you can get unqualified column names:

Orders.Columns.Unqualified().ID  // generates: "id"

Use Case

This is particularly useful for ON CONFLICT clauses where you need column names without table prefix:

psql.Insert(...).
    OnConflict(Orders.Columns.Unqualified().ID).
    DoUpdate(...)

[stephenafamo]

If Unqualified is now the same as calling AliasedAs(""), do we really need an additional method?

I try to avoid adding new methods so there are less avenues for breaking changes

[atzedus]

If Unqualified is now the same as calling AliasedAs(""), do we really need an additional method?

I try to avoid adding new methods so there are less avenues for breaking changes

You're right that Unqualified() is functionally equivalent to AliasedAs(""). However, I believe there are good reasons to keep it:

1. Semantic clarity

Unqualified() clearly expresses intent, while AliasedAs("") looks like a magic value or potential bug. When reading code:

// Clear intent - "give me columns without table prefix"
Orders.Columns.Unqualified()

// Confusing - "why empty string? Is this a mistake?"
Orders.Columns.AliasedAs("")

2. It affects ColumnsExpr methods, not just individual column expressions

The key difference is that Unqualified() returns columns where ColumnsExpr.parent is empty. This affects methods like Only(), Except(), WithPrefix() that operate on the embedded ColumnsExpr:

// With Unqualified() - generates: "id", "name" (no table prefix)
Orders.Columns.Unqualified().Only("id", "name")

// The parent slice is empty, so WriteSQL produces clean column list
// Useful for INSERT column lists, ON CONFLICT targets, etc.

3. Discoverability

Users looking for "how to get columns without table name" will find Unqualified() through autocomplete. They won't think to try AliasedAs("").

That said, I understand your concern about API surface. If you prefer, we could:

• Document AliasedAs("") as the way to get unqualified columns
• Or keep Unqualified() as a convenience method that's unlikely to need breaking changes

What do you think?

[stephenafamo]

Alright, let's add Unqualified()

[stephenafamo]

Just a little nitpick