fix generated columns in mutable columns for PostgreSQL

Fix https://github.com/go-jet/jet/issues/209.

generator/metadata/column_meta_data.go

@@ -5,6 +5,7 @@ type Column struct {
 	Name         string
 	IsPrimaryKey bool
 	IsNullable   bool
+	IsGenerated  bool
 	DataType     DataType
 }
 

generator/metadata/table_meta_data.go

@@ -11,7 +11,7 @@ func (t Table) MutableColumns() []Column {
 	var ret []Column
 
 	for _, column := range t.Columns {
-		if column.IsPrimaryKey {
+		if column.IsPrimaryKey || column.IsGenerated {
 			continue
 		}
 

generator/postgres/query_set.go

@@ -44,6 +44,7 @@ WITH primaryKeys AS (
 )
 SELECT column_name as "column.Name", 
 	   is_nullable = 'YES' as "column.isNullable",
+	   is_generated = 'ALWAYS' as "column.isGenerated",
 	   (EXISTS(SELECT 1 from primaryKeys as pk where pk.column_name = columns.column_name)) as "column.IsPrimaryKey",
 	   dataType.kind as "dataType.Kind",	
 	   (case dataType.Kind when 'base' then data_type else LTRIM(udt_name, '_') end) as "dataType.Name",