fix validateNoConflictingColumnNames input and add test case for table joining on itself without an alias

Author: angelamayxie

enginetest/queries/update_queries.go

@@ -943,6 +943,11 @@ var UpdateErrorTests = []QueryErrorTest{
 		Query:       `UPDATE people SET height_inches = IF(ROW_NUMBER() OVER() % 2 = 0, 42, height_inches)`,
 		ExpectedErr: sql.ErrWindowUnsupported,
 	},
+	{
+		Query: `update people join people set height_inches = 100 where height_inches < 100`,
+		// TODO: mysql outputs sql.ErrDuplicateAliasOrTable error instead
+		ExpectedErr: sql.ErrAmbiguousColumnName,
+	},
 }
 
 var UpdateErrorScripts = []ScriptTest{

sql/analyzer/triggers.go

@@ -483,7 +483,7 @@ func getTriggerLogic(ctx *sql.Context, a *Analyzer, n sql.Node, scope *plan.Scop
 		} else {
 			// TODO: We should be able to handle duplicate column names by masking columns that aren't part of the
 			// triggered table https://github.com/dolthub/dolt/issues/9403
-			err = validateNoConflictingColumnNames(updateSrc.Child)
+			err = validateNoConflictingColumnNames(updateSrc.Child.Schema())
 			if err != nil {
 				return nil, err
 			}