beego - Simple & powerful Go App framework

This feture is for database migration and auto-create tables.

Struct Tag

orm:"null;rel(fk)"

Every field of struct tag contains 2 kinds of setting types. Multiple settings use ; to separate, or use , to separate multiple values.

Omit fields

Use - to omit fields of struct:

type User struct {
...
    AnyField string `orm:"-"`
...

auto

Set as Auto-increment Primary Key.

pk

Set as Primary Key。

null

Database tables use NOT NULL as default, set them to null means ALLOW NULL.

blank

Allow string type fields can be empty, otherwise error occurs when clean operation.

index

Add index for fields.

unique

Add unique key for fields.

column

Set database column name for fields:

Name `orm:"column(user_name)"`

default

Set default value of fields with same type:

type User struct {
    ...
    Status int `orm:"default(1)"`

size (string)

After setting size of string type fields, the type of fields will be varchar in database:

Title string `orm:"size(60)"`

digits / decimals

Setting length and decimal of float32, float64:

Money float64 `orm:"digits(12);decimals(4)"`

Total length is 12 and 4 decimals: 99999999.9999.

auto_now / auto_now_add

Created     time.Time `auto_now_add`
Updated     time.Time `auto_now`

auto_now: auto-update time when saved.
auto_now_add: update time once when created.

This setting will not work when you do batch update.

type

Type date and time.Time are mapping to date type in database:

Created time.Time `orm:"auto_now_add;type(date)"`

Table relation

rel / reverse

RelOneToOne:

type User struct {
    ...
    Profile *Profi  le `orm:"null;rel(one);on_delete(set_null)"`

Corresponding reverse relation RelReverseOne:

type Profile struct {
    ...
    User *User `orm:"reverse(one)"`

RelForeignKey:

type Post struct {
    ...
    User*User `orm:"rel(fk)"` // RelForeignKey relation

Corresponding reverse relation RelReverseMany:

type User struct {
    ...
    Posts []*Post `orm:"reverse(many)"` // fk 的反向关系

RelManyToMany:

type Post struct {
    ...
    Tags []*Tag `orm:"rel(m2m)"` // ManyToMany relation

Corresponding reverse relation RelReverseMany:

type Tag struct {
    ...
    Posts []*Post `orm:"reverse(many)"`

rel_table / rel_through

This setting is for relation fields that uses orm:"rel(m2m)":

rel_table       Auto-generate m2m relation table name
rel_through     If you want to use customize m2m relation tables in m2m                     relation, you have to set this with format pkg.path.ModelName
                eg: app.models.PostTagRel
                Table PostTagRel need have relation Post and Tag.

rel_through will be omitted after you setting rel_table.

on_delete

This describes how to deal with relation fields when one of them have delete operation:

cascade        default
set_null       use `null = true` to set to NULL
set_default    set as default, need to set default value
do_nothing

type User struct {
    ...
    Profile *Profile `orm:"null;rel(one);on_delete(set_null)"`
...
type Profile struct {
    ...
    User *User `orm:"reverse(one)"`

// User.Profile will be setting to NULL after Profile was deleted.

Mapping of model type and database type

This standard will work for auto-create table.

All fields are NOT NULL as default.

MySQL

go	mysql
bool	bool
string - when setting size	varchar(size)
string	longtext
time.Time - when setting type to date	date
time.TIme	datetime
byte	tinyint unsigned
rune	integer
int	integer
int8	tinyint
int16	smallint
int32	integer
int64	bigint
uint	integer unsigned
uint8	tinyint unsigned
uint16	smallint unsigned
uint32	integer unsigned
uint64	bigint unsigned
float32	double precision
float64	double precision
float64 - when setting digits and decimals	numeric(digits, decimals)

Sqlite3

go	sqlite3
bool	bool
string - when setting size	varchar(size)
string	text
time.Time - when setting type to date	date
time.TIme	datetime
byte	tinyint unsigned
rune	integer
int	integer
int8	tinyint
int16	smallint
int32	integer
int64	bigint
uint	integer unsigned
uint8	tinyint unsigned
uint16	smallint unsigned
uint32	integer unsigned
uint64	bigint unsigned
float32	real
float64	real
float64 - when setting digits and decimals	decimal

PostgreSQL

go	postgres
bool	bool
string - when setting size	varchar(size)
string	text
time.Time - when setting type to date	date
time.TIme	timestamp with time zone
byte	smallint CHECK(“column” >= 0 AND “column” <= 255)
rune	integer
int	integer
int8	smallint CHECK(“column” >= -127 AND “column” <= 128)
int16	smallint
int32	integer
int64	bigint
uint	bigint CHECK(“column” >= 0)
uint8	smallint CHECK(“column” >= 0 AND “column” <= 255)
uint16	integer CHECK(“column” >= 0)
uint32	bigint CHECK(“column” >= 0)
uint64	bigint CHECK(“column” >= 0)
float32	double precision
float64	double precision
float64 - when setting digits and decimals	numeric(digits, decimals)

Relational fields

The field type is depending on its primary key:

RelForeignKey
RelOneToOne
RelManyToMany
RelReverseOne
RelReverseMany

Models