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", 

tests/Makefile

@@ -47,6 +47,7 @@ jet-gen-postgres:
 	jet -dsn=postgres://jet:jet@localhost:50901/jetdb?sslmode=disable -schema=chinook2  -path=./.gentestdata/
 	jet -dsn=postgres://jet:jet@localhost:50901/jetdb?sslmode=disable -schema=northwind  -path=./.gentestdata/
 	jet -dsn=postgres://jet:jet@localhost:50901/jetdb?sslmode=disable -schema=test_sample  -path=./.gentestdata/
+	jet -dsn=postgres://jet:jet@localhost:50901/jetdb?sslmode=disable -schema=test_generated  -path=./.gentestdata/
 
 jet-gen-mysql:
 	jet -source=mysql -dsn="jet:jet@tcp(localhost:50902)/dvds" -path=./.gentestdata/mysql

tests/init/init.go

@@ -134,6 +134,7 @@ func initPostgresDB(dbType string, connectionString string) {
 		"test_sample",
 		"chinook",
 		"chinook2",
+		"test_generated",
 	}
 
 	for _, schemaName := range schemaNames {

tests/postgres/generated_test.go

@@ -0,0 +1,15 @@
+package postgres
+
+import (
+	. "github.com/go-jet/jet/v2/tests/.gentestdata/jetdb/test_generated/table"
+	"github.com/stretchr/testify/require"
+	"testing"
+)
+
+func TestMutableColumnsExcludeGeneratedColumn(t *testing.T) {
+	t.Run("should not have the generated column in mutableColumns", func(t *testing.T) {
+		require.Equal(t, 2, len(People.MutableColumns))
+		require.Equal(t, People.PeopleName, People.MutableColumns[0])
+		require.Equal(t, People.PeopleHeightCm, People.MutableColumns[1])
+	})
+}