diff --git a/err.go b/err.go
index bbd9216..b0bb87c 100644
--- a/err.go
+++ b/err.go
@@ -7,11 +7,11 @@ type ErrController struct {
 	Err error
 }
 
-func (e *ErrController) Error() string {
+func (e ErrController) Error() string {
 	return e.Err.Error()
 }
 
-func (e *ErrController) Unwrap() error {
+func (e ErrController) Unwrap() error {
 	return e.Err
 }
 
diff --git a/internal.go b/internal.go
index 5495758..9f42636 100644
--- a/internal.go
+++ b/internal.go
@@ -5,7 +5,7 @@ import (
 )
 
 // initHelpers creates all the Struct2sql objects. For HTTP endpoints, it is necessary to create these first
-func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerOptions) *ErrController {
+func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerOptions) error {
 	obj := newObjFunc()
 
 	var forceName string
@@ -15,7 +15,7 @@ func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerO
 
 	cErr := c.orm.RegisterStruct(obj, nil, false, forceName, false)
 	if cErr != nil {
-		return &ErrController{
+		return ErrController{
 			Op:  "RegisterStruct",
 			Err: fmt.Errorf("Error adding SQL generator: %w", cErr.Unwrap()),
 		}
@@ -24,7 +24,7 @@ func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerO
 	if options.CreateConstructor != nil {
 		cErr = c.orm.RegisterStruct(options.CreateConstructor(), obj, false, "", true)
 		if cErr != nil {
-			return &ErrController{
+			return ErrController{
 				Op:  "RegisterStruct",
 				Err: fmt.Errorf("Error adding SQL generator: %w", cErr.Unwrap()),
 			}
@@ -34,7 +34,7 @@ func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerO
 	if options.ReadConstructor != nil {
 		cErr = c.orm.RegisterStruct(options.ReadConstructor(), obj, false, "", true)
 		if cErr != nil {
-			return &ErrController{
+			return ErrController{
 				Op:  "RegisterStruct",
 				Err: fmt.Errorf("Error adding SQL generator: %w", cErr.Unwrap()),
 			}
@@ -44,7 +44,7 @@ func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerO
 	if options.UpdateConstructor != nil {
 		cErr = c.orm.RegisterStruct(options.UpdateConstructor(), obj, false, "", true)
 		if cErr != nil {
-			return &ErrController{
+			return ErrController{
 				Op:  "RegisterStruct",
 				Err: fmt.Errorf("Error adding SQL generator: %w", cErr.Unwrap()),
 			}
@@ -54,7 +54,7 @@ func (c *Controller) initHelpers(newObjFunc func() interface{}, options HandlerO
 	if options.ListConstructor != nil {
 		cErr = c.orm.RegisterStruct(options.ListConstructor(), obj, false, "", true)
 		if cErr != nil {
-			return &ErrController{
+			return ErrController{
 				Op:  "RegisterStruct",
 				Err: fmt.Errorf("Error adding SQL generator: %w", cErr.Unwrap()),
 			}
diff --git a/internal_http.go b/internal_http.go
index e73e3d0..3352af5 100644
--- a/internal_http.go
+++ b/internal_http.go
@@ -183,7 +183,7 @@ func (c Controller) handleHTTPGet(w http.ResponseWriter, r *http.Request, newObj
 			}
 			continue
 		}
-		if errF.Op == "GetHelper" {
+		if errF.(ErrController).Op == "GetHelper" {
 			c.writeErrText(w, http.StatusInternalServerError, "get_helper")
 			return
 		} else {
@@ -293,10 +293,10 @@ func (c Controller) jsonID(id int64) []byte {
 	return []byte(fmt.Sprintf("{\"id\":\"%d\"}", id))
 }
 
-func (c Controller) uriFilterToFilter(obj interface{}, filterName string, filterValue string) (string, interface{}, *ErrController) {
+func (c Controller) uriFilterToFilter(obj interface{}, filterName string, filterValue string) (string, interface{}, error) {
 	fieldName, cErr := c.orm.GetFieldNameFromDBCol(obj, filterName)
 	if cErr != nil {
-		return "", nil, &ErrController{
+		return "", nil, ErrController{
 			Op:  "GetDBCol",
 			Err: fmt.Errorf("Error getting field name from filter: %w", cErr),
 		}
@@ -311,7 +311,7 @@ func (c Controller) uriFilterToFilter(obj interface{}, filterName string, filter
 	if valueField.Type().Name() == "int" {
 		filterInt, err := strconv.Atoi(filterValue)
 		if err != nil {
-			return "", nil, &ErrController{
+			return "", nil, ErrController{
 				Op:  "InvalidValue",
 				Err: fmt.Errorf("Error converting string to int: %w", err),
 			}
@@ -321,7 +321,7 @@ func (c Controller) uriFilterToFilter(obj interface{}, filterName string, filter
 	if valueField.Type().Name() == "int64" {
 		filterInt64, err := strconv.ParseInt(filterValue, 10, 64)
 		if err != nil {
-			return "", nil, &ErrController{
+			return "", nil, ErrController{
 				Op:  "InvalidValue",
 				Err: fmt.Errorf("Error converting string to int64: %w", err),
 			}
diff --git a/main_test.go b/main_test.go
index 3992d41..a5e7b31 100644
--- a/main_test.go
+++ b/main_test.go
@@ -330,9 +330,6 @@ func makePUTInsertRequest(j string, status int, t *testing.T) []byte {
 		t.Fatalf("PUT method failed on HTTP server with handler from GetHTTPHandler: %s", err.Error())
 	}
 	if resp.StatusCode != status {
-		b, _ := io.ReadAll(resp.Body)
-		log.Printf("url: %s", url)
-		log.Printf("response body: %s", string(b))
 		t.Fatalf("PUT method returned wrong status code, want %d, got %d", status, resp.StatusCode)
 	}
 
@@ -361,10 +358,6 @@ func makePUTUpdateRequest(j string, id int64, customURI string, t *testing.T) []
 		t.Fatalf("PUT method failed on HTTP server with handler from GetHTTPHandler: %s", err.Error())
 	}
 	if resp.StatusCode != http.StatusOK {
-		b, _ := io.ReadAll(resp.Body)
-		log.Printf("url: %s", url)
-		log.Printf("response body: %s", string(b))
-
 		t.Fatalf("PUT method returned wrong status code, want %d, got %d", http.StatusOK, resp.StatusCode)
 	}
 
diff --git a/orm.go b/orm.go
index d44a516..8fe0355 100644
--- a/orm.go
+++ b/orm.go
@@ -2,6 +2,7 @@ package crud
 
 import (
 	"database/sql"
+	"errors"
 
 	struct2db "github.com/go-phings/struct-db-postgres"
 )
@@ -11,6 +12,8 @@ type ORMError interface {
 	IsInvalidFilters() bool
 	// Unwraps unwarps the original error
 	Unwrap() error
+	// Error returns error string
+	Error() string
 }
 
 type ORM interface {
@@ -58,15 +61,15 @@ type ormErrorImpl struct {
 	err error
 }
 
-func (o *ormErrorImpl) IsInvalidFilters() bool {
+func (o ormErrorImpl) IsInvalidFilters() bool {
 	return o.op == "ValidateFilters"
 }
 
-func (o *ormErrorImpl) Error() string {
+func (o ormErrorImpl) Error() string {
 	return o.err.Error()
 }
 
-func (o *ormErrorImpl) Unwrap() error {
+func (o ormErrorImpl) Unwrap() error {
 	return o.err
 }
 
@@ -78,19 +81,35 @@ type wrappedStruct2db struct {
 }
 
 func (w *wrappedStruct2db) CreateTables(objs ...interface{}) error {
-	return w.orm.CreateTables(objs...)
+	err := w.orm.CreateTables(objs...)
+	if err != nil {
+		return errors.New("create table failed")
+	}
+	return nil
 }
 
 func (w *wrappedStruct2db) Load(obj interface{}, id string) error {
-	return w.orm.Load(obj, id, struct2db.LoadOptions{})
+	err := w.orm.Load(obj, id, struct2db.LoadOptions{})
+	if err != nil {
+		return errors.New("load failed")
+	}
+	return nil
 }
 
 func (w *wrappedStruct2db) Save(obj interface{}) error {
-	return w.orm.Save(obj, struct2db.SaveOptions{})
+	err := w.orm.Save(obj, struct2db.SaveOptions{})
+	if err != nil {
+		return errors.New("save failed")
+	}
+	return nil
 }
 
 func (w *wrappedStruct2db) Delete(obj interface{}) error {
-	return w.orm.Delete(obj, struct2db.DeleteOptions{})
+	err := w.orm.Delete(obj, struct2db.DeleteOptions{})
+	if err != nil {
+		return errors.New("delete failed")
+	}
+	return nil
 }
 
 func (w *wrappedStruct2db) Get(newObjFunc func() interface{}, order []string, limit int, offset int, filters map[string]interface{}, rowObjTransformFunc func(interface{}) interface{}) ([]interface{}, ORMError) {
@@ -103,13 +122,13 @@ func (w *wrappedStruct2db) Get(newObjFunc func() interface{}, order []string, li
 	})
 
 	if err != nil && err.Op == "ValidateFilters" {
-		return nil, &ormErrorImpl{
+		return nil, ormErrorImpl{
 			op: err.Op,
 		}
 	}
 
 	if err != nil {
-		return nil, &ormErrorImpl{
+		return nil, ormErrorImpl{
 			op:  err.Op,
 			err: err.Err,
 		}
@@ -119,7 +138,11 @@ func (w *wrappedStruct2db) Get(newObjFunc func() interface{}, order []string, li
 }
 
 func (w *wrappedStruct2db) GetFieldNameFromDBCol(obj interface{}, field string) (string, error) {
-	return w.orm.GetFieldNameFromDBCol(obj, field)
+	s, e := w.orm.GetFieldNameFromDBCol(obj, field)
+	if e != nil {
+		return "", errors.New("error getting field name from db col")
+	}
+	return s, nil
 }
 
 func (w *wrappedStruct2db) GetObjIDValue(obj interface{}) int64 {
@@ -133,7 +156,7 @@ func (w *wrappedStruct2db) ResetFields(obj interface{}) {
 func (w *wrappedStruct2db) RegisterStruct(obj interface{}, inheritFromObj interface{}, overwriteExisting bool, forceNameForDB string, useOnlyRootFromInheritedObj bool) ORMError {
 	err := w.orm.AddSQLGenerator(obj, inheritFromObj, overwriteExisting, forceNameForDB, useOnlyRootFromInheritedObj)
 	if err != nil {
-		return &ormErrorImpl{
+		return ormErrorImpl{
 			op:  err.Op,
 			err: err.Err,
 		}