Function RemoveColumn

pkg/transform/columns.go:57–78

RemoveColumn returns a Rule that removes the first column in the SELECT list that matches name. Matching is case-insensitive and checks both identifier names and expression aliases. Returns an error if no column matching name is found, or ErrUnsupportedStatement for non-SELECT statements.

(name string)

// Returns an error if no column matching name is found, or ErrUnsupportedStatement
// for non-SELECT statements.
func RemoveColumn(name string) Rule {
	return RuleFunc(func(stmt ast.Statement) error {
		sel, err := getSelect(stmt, "RemoveColumn")
		if err != nil {
			return err
		}
		filtered := make([]ast.Expression, 0, len(sel.Columns))
		found := false
		for _, col := range sel.Columns {
			if columnMatches(col, name) {
				found = true
			} else {
				filtered = append(filtered, col)
			}
		}
		if !found {
			return fmt.Errorf("column %q not found", name)
		}
		sel.Columns = filtered
		return nil
	})
}

// ReplaceColumn returns a Rule that replaces every column in the SELECT list that
// matches oldName with a bare *ast.Identifier for newName. Matching is