orm now use a filed named `Id` as default auto primary key, you can ignore `orm:"auto"` setting

@@ -32,8 +32,26 @@ func registerModel(model interface{}) {
 	}
 
 	if info.fields.pk == nil {
-		fmt.Printf("<orm.RegisterModel> `%s` need a primary key field\n", name)
-		os.Exit(2)
+	outFor:
+		for _, fi := range info.fields.fieldsDB {
+			if fi.name == "Id" {
+				if fi.sf.Tag.Get(defaultStructTagName) == "" {
+					switch fi.addrValue.Elem().Kind() {
+					case reflect.Int, reflect.Int64, reflect.Int32:
+						fi.auto = true
+						fi.pk = true
+						info.fields.pk = fi
+						break outFor
+					}
+				}
+			}
+		}
+
+		if info.fields.pk == nil {
+			fmt.Printf("<orm.RegisterModel> `%s` need a primary key field\n", name)
+			os.Exit(2)
+		}
+
 	}
 
 	info.table = table

@@ -89,7 +89,7 @@ type fieldInfo struct {
 	fullName            string
 	column              string
 	addrValue           reflect.Value
-	sf                  *reflect.StructField
+	sf                  reflect.StructField
 	auto                bool
 	pk                  bool
 	null                bool
@@ -244,7 +244,7 @@ checkType:
 	fi.name = sf.Name
 	fi.column = getColumnName(fieldType, addrField, sf, tags["column"])
 	fi.addrValue = addrField
-	fi.sf = &sf
+	fi.sf = sf
 	fi.fullName = mi.fullName + "." + sf.Name
 
 	fi.null = attrs["null"]
@@ -358,6 +358,14 @@ checkType:
 
 	if fi.auto || fi.pk {
 		if fi.auto {
+
+			switch addrField.Elem().Kind() {
+			case reflect.Int, reflect.Int32, reflect.Int64:
+			default:
+				err = fmt.Errorf("auto primary key only support int, int32, int64, but found `%s`", addrField.Elem().Kind())
+				goto end
+			}
+
 			fi.pk = true
 		}
 		fi.null = false

@@ -13,10 +13,10 @@ import (
 )
 
 type Data struct {
-	Id       int `orm:"auto"`
+	Id       int
 	Boolean  bool
-	Char     string `orm:"size(50)"`
-	Text     string
+	Char     string    `orm:size(50)`
+	Text     string    `orm:"type(text)"`
 	Date     time.Time `orm:"type(date)"`
 	DateTime time.Time
 	Byte     byte
@@ -37,10 +37,10 @@ type Data struct {
 }
 
 type DataNull struct {
-	Id       int       `orm:"auto"`
+	Id       int
 	Boolean  bool      `orm:"null"`
 	Char     string    `orm:"size(50);null"`
-	Text     string    `orm:"null"`
+	Text     string    `orm:"type(text);null"`
 	Date     time.Time `orm:"type(date);null"`
 	DateTime time.Time `orm:"null"`
 	Byte     byte      `orm:"null"`
@@ -61,7 +61,7 @@ type DataNull struct {
 }
 
 type User struct {
-	Id         int    `orm:"auto"`
+	Id         int
 	UserName   string `orm:"size(30);unique"`
 	Email      string `orm:"size(100)"`
 	Password   string `orm:"size(100)"`
@@ -81,10 +81,10 @@ func NewUser() *User {
 }
 
 type Profile struct {
-	Id    int     `orm:"auto"`
-	Age   int16   ``
-	Money float64 ``
-	User  *User   `orm:"reverse(one)" json:"-"`
+	Id    int
+	Age   int16
+	Money float64
+	User  *User `orm:"reverse(one)" json:"-"`
 }
 
 func (u *Profile) TableName() string {
@@ -97,8 +97,8 @@ func NewProfile() *Profile {
 }
 
 type Post struct {
-	Id      int       `orm:"auto"`
-	User    *User     `orm:"rel(fk)"` //
+	Id      int
+	User    *User     `orm:"rel(fk)"`
 	Title   string    `orm:"size(60)"`
 	Content string    ``
 	Created time.Time `orm:"auto_now_add"`
@@ -112,7 +112,7 @@ func NewPost() *Post {
 }
 
 type Tag struct {
-	Id    int     `orm:"auto"`
+	Id    int
 	Name  string  `orm:"size(30)"`
 	Posts []*Post `orm:"reverse(many)" json:"-"`
 }
@@ -123,7 +123,7 @@ func NewTag() *Tag {
 }
 
 type Comment struct {
-	Id      int       `orm:"auto"`
+	Id      int
 	Post    *Post     `orm:"rel(fk)"`
 	Content string    ``
 	Parent  *Comment  `orm:"null;rel(fk)"`