admin.go

//db.go	
SELECT_DISTINCT_MASTER_TYPES               = "select distinct master_type from master_types"

//admin.go
master_type := Admin.AddResource(&models.MasterType{}, &admin.Config{
		Permission: configuration.GetPermission(C.MODEL_MASTER_TYPE),
		PageCount:  C.PAGE_COUNT})
	
master_type.Meta(&admin.Meta{
		Name:       "Master_Type",
		Type:       "select_one",
		Collection: getMasterTypeCollection,
	})

func getMasterTypeCollection(res interface{}, ctx *qor.Context) (results [][]string) {

	db := configuration.GetDB(C.READ)
	rows, err := db.Raw(C.SELECT_DISTINCT_MASTER_TYPES).Rows()
	if err == nil {
		defer rows.Close()
		for rows.Next() {
			var master models.MasterType
			db.ScanRows(rows, &master)
			results = append(results, []string{master.Master_Type, master.Master_Type})
		}
	} else {
		logs.GetLogger().Error("Error while getting distinct master_type from master_types table. %s", err)
		errors.New("Error while getting distinct master_type from master_types table.")
	}
	return results
}