restore index constructors

Author: asmyasnikov

table/example_test.go

@@ -80,7 +80,7 @@ func Example_createTable() {
 				),
 				options.WithIndex("idx_series_title",
 					options.WithIndexColumns("title"),
-					options.WithIndexType(options.IndexTypeGlobalAsync),
+					options.WithIndexType(options.GlobalAsyncIndex()),
 				),
 			)
 		},
@@ -166,7 +166,7 @@ func Example_alterTable() {
 				options.WithAddIndex("idx_series_series_id",
 					options.WithIndexColumns("series_id"),
 					options.WithDataColumns("title"),
-					options.WithIndexType(options.IndexTypeGlobalAsync),
+					options.WithIndexType(options.GlobalIndex()),
 				),
 				options.WithDropIndex("idx_series_title"),
 				options.WithAlterAttribute("hello", "world"),

table/options/models.go

@@ -289,6 +289,14 @@ func (t IndexType) ApplyIndexOption(d *indexDesc) {
 	}
 }
 
+func GlobalIndex() IndexType {
+	return IndexTypeGlobal
+}
+
+func GlobalAsyncIndex() IndexType {
+	return IndexTypeGlobalAsync
+}
+
 type PartitioningMode byte
 
 const (