fix: reset prepared stmts when table changed (#138)

go.mod

@@ -4,5 +4,5 @@ go 1.14
 
 require (
 	github.com/jackc/pgx/v4 v4.17.2
-	gorm.io/gorm v1.23.7
+	gorm.io/gorm v1.24.1-0.20221019064659-5dd2bb482755
 )

go.sum

@@ -192,4 +192,6 @@ gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gorm.io/gorm v1.23.7 h1:ww+9Mu5WwHKDSOQZFC4ipu/sgpKMr9EtrJ0uwBqNtB0=
 gorm.io/gorm v1.23.7/go.mod h1:l2lP/RyAtc1ynaTjFksBde/O8v9oOGIApu2/xRitmZk=
+gorm.io/gorm v1.24.1-0.20221019064659-5dd2bb482755 h1:7AdrbfcvKnzejfqP5g37fdSZOXH/JvaPIzBIHTOqXKk=
+gorm.io/gorm v1.24.1-0.20221019064659-5dd2bb482755/go.mod h1:DVrVomtaYTbqs7gB/x2uVvqnXzv0nqjB396B8cG4dBA=
 honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=

migrator.go

@@ -197,6 +197,8 @@ func (m Migrator) AddColumn(value interface{}, field string) error {
 	if err := m.Migrator.AddColumn(value, field); err != nil {
 		return err
 	}
+	m.resetPreparedStmts()
+
 	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
 		if field := stmt.Schema.LookUpField(field); field != nil {
 			if field.Comment != "" {
@@ -266,7 +268,7 @@ func (m Migrator) MigrateColumn(value interface{}, field *schema.Field, columnTy
 
 // AlterColumn alter value's `field` column' type based on schema definition
 func (m Migrator) AlterColumn(value interface{}, field string) error {
-	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
+	err := m.RunWithValue(value, func(stmt *gorm.Statement) error {
 		if field := stmt.Schema.LookUpField(field); field != nil {
 			var (
 				columnTypes, _  = m.DB.Migrator().ColumnTypes(value)
@@ -347,6 +349,12 @@ func (m Migrator) AlterColumn(value interface{}, field string) error {
 		}
 		return fmt.Errorf("failed to look up field with name: %s", field)
 	})
+
+	if err != nil {
+		return err
+	}
+	m.resetPreparedStmts()
+	return nil
 }
 
 func (m Migrator) HasConstraint(value interface{}, name string) bool {
@@ -694,3 +702,30 @@ func groupByIndexName(indexList []*Index) map[string][]*Index {
 func (m Migrator) GetTypeAliases(databaseTypeName string) []string {
 	return typeAliasMap[databaseTypeName]
 }
+
+// should reset prepared stmts when table changed
+func (m Migrator) resetPreparedStmts() {
+	if m.DB.PrepareStmt {
+		if pdb, ok := m.DB.ConnPool.(*gorm.PreparedStmtDB); ok {
+			pdb.Reset()
+		}
+	}
+}
+
+func (m Migrator) DropColumn(dst interface{}, field string) error {
+	if err := m.Migrator.DropColumn(dst, field); err != nil {
+		return err
+	}
+
+	m.resetPreparedStmts()
+	return nil
+}
+
+func (m Migrator) RenameColumn(dst interface{}, oldName, field string) error {
+	if err := m.Migrator.RenameColumn(dst, oldName, field); err != nil {
+		return err
+	}
+
+	m.resetPreparedStmts()
+	return nil
+}