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README.md
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README.md
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@ -19,11 +19,12 @@ Yet Another ORM library for Go, aims for developer friendly
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## Conventions
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## Conventions
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```go
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```go
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type User struct { // TableName: `users`, gorm will pluralize struct's name as table name
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// TableName: `users`, gorm will pluralize struct's name as table name, you are possible to turn off this feature
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type User struct {
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Id int64 // Id: Database Primary key
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Id int64 // Id: Database Primary key
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Birthday time.Time
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Birthday time.Time
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Age int64
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Age int64
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Name string `sql:"size:255"` // set this field's length and as not null with tag
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Name string `sql:"size:255"` // set this field's length in database
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CreatedAt time.Time // Time of record is created, will be insert automatically
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CreatedAt time.Time // Time of record is created, will be insert automatically
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UpdatedAt time.Time // Time of record is updated, will be updated automatically
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UpdatedAt time.Time // Time of record is updated, will be updated automatically
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DeletedAt time.Time // Time of record is deleted, refer `Soft Delete` for more
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DeletedAt time.Time // Time of record is deleted, refer `Soft Delete` for more
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@ -33,22 +34,22 @@ type User struct { // TableName: `users`, gorm will pluralize struct's n
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BillingAddressId sql.NullInt64 // Embedded struct BillingAddress's foreign key
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BillingAddressId sql.NullInt64 // Embedded struct BillingAddress's foreign key
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ShippingAddress Address // Embedded struct
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ShippingAddress Address // Embedded struct
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ShippingAddressId int64 // Embedded struct ShippingAddress's foreign key
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ShippingAddressId int64 // Embedded struct ShippingAddress's foreign key
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IgnoreMe int64 `sql:"-"` // Ignore this field with tag
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IgnoreMe int64 `sql:"-"` // Ignore this field
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}
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}
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type Email struct { // TableName: `emails`
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type Email struct { // TableName: `emails`
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Id int64
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Id int64
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UserId int64 // Foreign key for above embedded structs
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UserId int64 // Foreign key for above embedded structs
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Email string `sql:"type:varchar(100);"` // Set column type directly with tag
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Email string `sql:"type:varchar(100);"` // Set this field's type in database
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Subscribed bool
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Subscribed bool
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}
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}
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type Address struct { // TableName: `addresses`
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type Address struct { // TableName: `addresses`
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Id int64
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Id int64
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Address1 string `sql:"not null;unique"` // Set column as unique with tag
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Address1 string `sql:"not null;unique"` // Set this field as not null and unique in database
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Address2 string `sql:"type:varchar(100);unique"`
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Address2 string `sql:"type:varchar(100);unique"`
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Post sql.NullString `sql:not null`
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Post sql.NullString `sql:not null`
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// Be careful: "NOT NULL" will only works for NullXXX scanner, because golang will initalize a default value for most type...
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// FYI, "NOT NULL" will only works well with NullXXX Scanner, because golang will initalize a default value for most type...
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}
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}
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```
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```
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@ -69,20 +70,28 @@ db, err := Open("postgres", "user=gorm dbname=gorm sslmode=disable")
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db.SetPool(100)
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db.SetPool(100)
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// By default, table name is plural of struct type, if you like singular table name
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// By default, table name is plural of struct type, you can use struct type as table name with:
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db.SingularTable(true)
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db.SingularTable(true)
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// Gorm is goroutines friendly, so you can create a global variable to keep the connection and use it everywhere like this
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// Gorm is goroutines friendly, so you can create a global variable to keep the connection and use it everywhere in your project
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// db.go
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package db
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var DB gorm.DB
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var DB gorm.DB
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func init() {
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func init() {
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DB, err = gorm.Open("postgres", "user=gorm dbname=gorm sslmode=disable")
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DB, err = gorm.Open("postgres", "user=gorm dbname=gorm sslmode=disable")
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if err != nil {
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if err != nil {
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panic(fmt.Sprintf("Got error when connect database, the error is '%v'", err))
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panic(fmt.Sprintf("Got error when connect database, the error is '%v'", err))
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}
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}
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}
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}
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// user.go
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package user
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import _ "db"
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...
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DB.Save(&User{Name: "xxx"})
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...
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```
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```
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## Struct & Database Mapping
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## Struct & Database Mapping
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@ -99,9 +108,9 @@ db.DropTable(User{})
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Feel Free to update your struct, AutoMigrate will keep your database update to date.
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Feel Free to update your struct, AutoMigrate will keep your database update to date.
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FYI, AutoMigrate will only add new columns, won't change column's type or delete unused columns, to make sure gorm won't harm your data.
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FYI, AutoMigrate will only add new columns, won't change current column's type or delete unused columns, to make sure your data is safe
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If table doesn't exist when AutoMigrate, it will run create table automatically.
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If table doesn't exist when AutoMigrate, gorm will run create table automatically.
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(only postgres and mysql supported)
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(only postgres and mysql supported)
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@ -118,7 +127,7 @@ db.Save(&user)
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### Create With SubStruct
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### Create With SubStruct
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Refer [Query With Related](#query-with-related) to find how to find associations
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Refer [Query With Related](#query-with-related) for how to find associations
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```go
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```go
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user := User{
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user := User{
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@ -142,32 +151,22 @@ db.Save(&user)
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// Get the first record
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// Get the first record
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db.First(&user)
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db.First(&user)
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//// SELECT * FROM users ORDER BY id LIMIT 1;
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//// SELECT * FROM users ORDER BY id LIMIT 1;
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// Search table `users` are guessed from the out struct type.
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// Search table `users` is guessed from struct's type
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// You are possible to specify the table name with Model() if no out struct for some methods like Pluck()
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// Or set table name with Table(), if so, it will ignore the out struct even have it. more details following.
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// Get the last record
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// Get the last record
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db.Last(&user)
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db.Last(&user)
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//// SELECT * FROM users ORDER BY id DESC LIMIT 1;
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//// SELECT * FROM users ORDER BY id DESC LIMIT 1;
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// Get a record without order by primary key
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db.Find(&user)
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//// SELECT * FROM users LIMIT 1;
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// Get first record as map
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db.First(&users)
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//// SELECT * FROM users LIMIT 1;
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// Get All records
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// Get All records
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db.Find(&users)
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db.Find(&users)
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//// SELECT * FROM users;
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//// SELECT * FROM users;
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// Using a Primary Key
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// Get record with primary key
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db.First(&user, 10)
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db.First(&user, 10)
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//// SELECT * FROM users WHERE id = 10;
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//// SELECT * FROM users WHERE id = 10;
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```
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```
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### Query With Where (SQL like condition)
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### Query With Where (SQL)
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```go
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```go
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// Get the first matched record
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// Get the first matched record
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@ -205,7 +204,7 @@ db.Where(&User{Name: "jinzhu", Age: 20}).First(&user)
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db.Where(map[string]interface{}{"name": "jinzhu", "age": 20}).Find(&users)
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db.Where(map[string]interface{}{"name": "jinzhu", "age": 20}).Find(&users)
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//// SELECT * FROM users WHERE name = "jinzhu" AND age = 20;
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//// SELECT * FROM users WHERE name = "jinzhu" AND age = 20;
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// IN For Primary Key
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// IN for primary Keys
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db.Where([]int64{20, 21, 22}).Find(&users)
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db.Where([]int64{20, 21, 22}).Find(&users)
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//// SELECT * FROM users WHERE id IN (20, 21, 22);
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//// SELECT * FROM users WHERE id IN (20, 21, 22);
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```
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```
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@ -221,18 +220,18 @@ db.Not("name", "jinzhu").First(&user)
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db.Not("name", []string{"jinzhu", "jinzhu 2"}).Find(&users)
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db.Not("name", []string{"jinzhu", "jinzhu 2"}).Find(&users)
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//// SELECT * FROM users WHERE name NOT IN ("jinzhu", "jinzhu 2");
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//// SELECT * FROM users WHERE name NOT IN ("jinzhu", "jinzhu 2");
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// Not In for Primary Key
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// Not In for primary keys
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db.Not([]int64{1,2,3}).First(&user)
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db.Not([]int64{1,2,3}).First(&user)
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//// SELECT * FROM users WHERE id NOT IN (1,2,3);
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//// SELECT * FROM users WHERE id NOT IN (1,2,3);
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db.Not([]int64{}).First(&user)
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db.Not([]int64{}).First(&user)
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//// SELECT * FROM users;
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//// SELECT * FROM users;
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// Normal SQL
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// SQL string
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db.Not("name = ?", "jinzhu").First(&user)
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db.Not("name = ?", "jinzhu").First(&user)
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//// SELECT * FROM users WHERE NOT(name = "jinzhu");
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//// SELECT * FROM users WHERE NOT(name = "jinzhu");
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// Not With Struct
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// Not with struct
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db.Not(User{Name: "jinzhu"}).First(&user)
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db.Not(User{Name: "jinzhu"}).First(&user)
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//// SELECT * FROM users WHERE name <> "jinzhu";
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//// SELECT * FROM users WHERE name <> "jinzhu";
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```
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```
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db.First(&user, 23)
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db.First(&user, 23)
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//// SELECT * FROM users WHERE id = 23 LIMIT 1;
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//// SELECT * FROM users WHERE id = 23 LIMIT 1;
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// Normal SQL
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// SQL string
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db.Find(&user, "name = ?", "jinzhu")
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db.Find(&user, "name = ?", "jinzhu")
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//// SELECT * FROM users WHERE name = "jinzhu";
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//// SELECT * FROM users WHERE name = "jinzhu";
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db.Find(&users, "name <> ? and age > ?", "jinzhu", 20)
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db.Find(&users, "name <> ? and age > ?", "jinzhu", 20)
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//// SELECT * FROM users WHERE name <> "jinzhu" AND age > 20;
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//// SELECT * FROM users WHERE name <> "jinzhu" AND age > 20;
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// Inline Search With Struct
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// Inline search with struct
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db.Find(&users, User{Age: 20})
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db.Find(&users, User{Age: 20})
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//// SELECT * FROM users WHERE age = 20;
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//// SELECT * FROM users WHERE age = 20;
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// Inline Search With Map
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// Inline search with map
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db.Find(&users, map[string]interface{}{"age": 20})
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db.Find(&users, map[string]interface{}{"age": 20})
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//// SELECT * FROM users WHERE age = 20;
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//// SELECT * FROM users WHERE age = 20;
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```
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```
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### Query With Related
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### Query With Related
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```go
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```go
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// Find emails from user with guessed foreign key
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// Find user's emails with guessed foreign key
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db.Model(&user).Related(&emails)
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db.Model(&user).Related(&emails)
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//// SELECT * FROM emails WHERE user_id = 111;
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//// SELECT * FROM emails WHERE user_id = 111;
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// Find address from user with specified foreign key 'BillingAddressId'
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// Find user's billing address with specified foreign key 'BillingAddressId'
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db.Model(&user).Related(&address1, "BillingAddressId")
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db.Model(&user).Related(&address1, "BillingAddressId")
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//// SELECT * FROM addresses WHERE id = 123; // 123 is the value of user's BillingAddressId
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//// SELECT * FROM addresses WHERE id = 123; // 123 is user's BillingAddressId
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// Find user from email with guessed primary key value from emails
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// Find user with guessed primary key value from email
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db.Model(&email).Related(&user)
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db.Model(&email).Related(&user)
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//// SELECT * FROM users WHERE id = 111; // 111 is the value of email's UserId
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//// SELECT * FROM users WHERE id = 111; // 111 is email's UserId
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```
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```
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### Query Chains
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### Query Chains
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@ -316,16 +315,16 @@ db.Save(&user)
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### Update one attribute with `Update`
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### Update one attribute with `Update`
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```go
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```go
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// Update an existing struct's name if name is different
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// Update existing user's name if it is changed
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db.Model(&user).Update("name", "hello")
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db.Model(&user).Update("name", "hello")
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//// UPDATE users SET name='hello' WHERE id=111;
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//// UPDATE users SET name='hello' WHERE id=111;
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// Find out a struct, and update it if name is different
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// Find out a user, and update the name if it is changed
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db.First(&user, 111).Update("name", "hello")
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db.First(&user, 111).Update("name", "hello")
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//// SELECT * FROM users LIMIT 1;
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//// SELECT * FROM users LIMIT 1;
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//// UPDATE users SET name='hello' WHERE id=111;
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//// UPDATE users SET name='hello' WHERE id=111;
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// Specify table name with where search
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// Update name with search condiation and specified table name
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db.Table("users").Where(10).Update("name", "hello")
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db.Table("users").Where(10).Update("name", "hello")
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//// UPDATE users SET name='hello' WHERE id = 10;
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//// UPDATE users SET name='hello' WHERE id = 10;
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```
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```
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@ -333,7 +332,7 @@ db.Table("users").Where(10).Update("name", "hello")
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### Update multiple attributes with `Updates`
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### Update multiple attributes with `Updates`
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```go
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```go
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// Update an existing record if have any changed values
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// Update user's name and age if they are changed
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db.Model(&user).Updates(User{Name: "hello", Age: 18})
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db.Model(&user).Updates(User{Name: "hello", Age: 18})
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//// UPDATE users SET name='hello', age=18 WHERE id = 111;
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//// UPDATE users SET name='hello', age=18 WHERE id = 111;
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db.Delete(&user)
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db.Delete(&user)
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//// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE id = 111;
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//// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE id = 111;
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// Batch delete when search
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// Delete with search condiation
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db.Where("age = ?", 20).Delete(&User{})
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db.Where("age = ?", 20).Delete(&User{})
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//// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE age = 20;
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//// UPDATE users SET deleted_at="2013-10-29 10:23" WHERE age = 20;
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// For structs have DeletedAt field, when do query, will ignore deleted records by default
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// Soft deleted records will be ignored when search
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db.Where("age = 20").Find(&user)
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db.Where("age = 20").Find(&user)
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//// SELECT * FROM users WHERE age = 100 AND (deleted_at IS NULL AND deleted_at <= '0001-01-02');
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//// SELECT * FROM users WHERE age = 100 AND (deleted_at IS NULL AND deleted_at <= '0001-01-02');
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// Find out all records including those deleted with Unscoped
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// Find soft deleted records with Unscoped
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db.Unscoped().Where("age = 20").Find(&users)
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db.Unscoped().Where("age = 20").Find(&users)
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//// SELECT * FROM users WHERE age = 20;
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//// SELECT * FROM users WHERE age = 20;
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// Permanently delete a record with Unscoped
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// Delete record permanently with Unscoped
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db.Unscoped().Delete(&order)
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db.Unscoped().Delete(&order)
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// DELETE FROM orders WHERE id=10;
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// DELETE FROM orders WHERE id=10;
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```
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```
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## FirstOrInit
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## FirstOrInit
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Try to load the first record, if fails, initialize struct with search conditions.
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Try to get the first record, if failed, will initialize the struct with search conditions.
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(only support map or struct conditions, SQL like conditions are not supported)
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(only support search conditions map and struct)
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```go
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```go
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db.FirstOrInit(&user, User{Name: "non_existing"})
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db.FirstOrInit(&user, User{Name: "non_existing"})
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@ -408,17 +407,17 @@ db.FirstOrInit(&user, map[string]interface{}{"name": "jinzhu"})
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### FirstOrInit With Attrs
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### FirstOrInit With Attrs
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Attr's arguments would be used to initialize struct if no record found, but won't be used for search
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Ignore Attrs's arguments when search, but use them to initialize the struct if no record found.
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```go
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```go
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db.Where(User{Name: "non_existing"}).Attrs(User{Age: 20}).FirstOrInit(&user)
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db.Where(User{Name: "non_existing"}).Attrs(User{Age: 20}).FirstOrInit(&user)
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//// SELECT * FROM USERS WHERE name = 'non_existing';
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//// SELECT * FROM USERS WHERE name = 'non_existing';
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//// User{Name: "non_existing", Age: 20}
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//// User{Name: "non_existing", Age: 20}
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// Above code could be simplified if has only one attribute
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// Or write it like this if has only one attribute
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db.Where(User{Name: "noexisting_user"}).Attrs("age", 20).FirstOrInit(&user)
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db.Where(User{Name: "noexisting_user"}).Attrs("age", 20).FirstOrInit(&user)
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// If a record found, Attrs would be just ignored
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// If a record found, Attrs would be ignored
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db.Where(User{Name: "Jinzhu"}).Attrs(User{Age: 30}).FirstOrInit(&user)
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db.Where(User{Name: "Jinzhu"}).Attrs(User{Age: 30}).FirstOrInit(&user)
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//// SELECT * FROM USERS WHERE name = jinzhu';
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//// SELECT * FROM USERS WHERE name = jinzhu';
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//// User{Id: 111, Name: "Jinzhu", Age: 20}
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//// User{Id: 111, Name: "Jinzhu", Age: 20}
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@ -426,7 +425,7 @@ db.Where(User{Name: "Jinzhu"}).Attrs(User{Age: 30}).FirstOrInit(&user)
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### FirstOrInit With Assign
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### FirstOrInit With Assign
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Assign's arguments would be used to set the struct even a record found, but won't be used for search
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Ignore Assign's arguments when search, but use them to fill the struct regardless record found or not
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```go
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```go
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db.Where(User{Name: "non_existing"}).Assign(User{Age: 20}).FirstOrInit(&user)
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db.Where(User{Name: "non_existing"}).Assign(User{Age: 20}).FirstOrInit(&user)
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@ -438,7 +437,7 @@ db.Where(User{Name: "Jinzhu"}).Assign(User{Age: 30}).FirstOrInit(&user)
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## FirstOrCreate
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## FirstOrCreate
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|
|
||||||
Try to load the first record, if fails, initialize struct with search conditions and save it
|
Try to get the first record, if failed, will initialize the struct with search conditions and insert it to database
|
||||||
|
|
||||||
```go
|
```go
|
||||||
db.FirstOrCreate(&user, User{Name: "non_existing"})
|
db.FirstOrCreate(&user, User{Name: "non_existing"})
|
||||||
|
@ -453,7 +452,7 @@ db.FirstOrCreate(&user, map[string]interface{}{"name": "jinzhu", "age": 30})
|
||||||
|
|
||||||
### FirstOrCreate With Attrs
|
### FirstOrCreate With Attrs
|
||||||
|
|
||||||
Attr's arguments would be used to initialize struct if no record found, but won't be used for search
|
Ignore Attrs's arguments when search, but use them to initialize the struct if no record found.
|
||||||
|
|
||||||
```go
|
```go
|
||||||
db.Where(User{Name: "non_existing"}).Attrs(User{Age: 20}).FirstOrCreate(&user)
|
db.Where(User{Name: "non_existing"}).Attrs(User{Age: 20}).FirstOrCreate(&user)
|
||||||
|
@ -466,9 +465,7 @@ db.Where(User{Name: "jinzhu"}).Attrs(User{Age: 30}).FirstOrCreate(&user)
|
||||||
|
|
||||||
### FirstOrCreate With Assign
|
### FirstOrCreate With Assign
|
||||||
|
|
||||||
Assign's arguments would be used to initialize the struct if not record found,
|
Ignore Assign's arguments when search, but use them to fill the struct regardless record found or not, then save it back to database
|
||||||
|
|
||||||
If any record found, will assign those values to the record, and save it back to database.
|
|
||||||
|
|
||||||
```go
|
```go
|
||||||
db.Where(User{Name: "non_existing"}).Assign(User{Age: 20}).FirstOrCreate(&user)
|
db.Where(User{Name: "non_existing"}).Assign(User{Age: 20}).FirstOrCreate(&user)
|
||||||
|
@ -493,6 +490,7 @@ db.Select("name, age").Find(&users)
|
||||||
db.Order("age desc, name").Find(&users)
|
db.Order("age desc, name").Find(&users)
|
||||||
//// SELECT * FROM users ORDER BY age desc, name;
|
//// SELECT * FROM users ORDER BY age desc, name;
|
||||||
|
|
||||||
|
// Multiple orders
|
||||||
db.Order("age desc").Order("name").Find(&users)
|
db.Order("age desc").Order("name").Find(&users)
|
||||||
//// SELECT * FROM users ORDER BY age desc, name;
|
//// SELECT * FROM users ORDER BY age desc, name;
|
||||||
|
|
||||||
|
@ -508,7 +506,7 @@ db.Order("age desc").Find(&users1).Order("age", true).Find(&users2)
|
||||||
db.Limit(3).Find(&users)
|
db.Limit(3).Find(&users)
|
||||||
//// SELECT * FROM users LIMIT 3;
|
//// SELECT * FROM users LIMIT 3;
|
||||||
|
|
||||||
// Cleanup limit with -1
|
// Remove limit with -1
|
||||||
db.Limit(10).Find(&users1).Limit(-1).Find(&users2)
|
db.Limit(10).Find(&users1).Limit(-1).Find(&users2)
|
||||||
//// SELECT * FROM users LIMIT 10; (users1)
|
//// SELECT * FROM users LIMIT 10; (users1)
|
||||||
//// SELECT * FROM users; (users2)
|
//// SELECT * FROM users; (users2)
|
||||||
|
@ -520,7 +518,7 @@ db.Limit(10).Find(&users1).Limit(-1).Find(&users2)
|
||||||
db.Offset(3).Find(&users)
|
db.Offset(3).Find(&users)
|
||||||
//// SELECT * FROM users OFFSET 3;
|
//// SELECT * FROM users OFFSET 3;
|
||||||
|
|
||||||
// Cleanup offset with -1
|
// Remove offset with -1
|
||||||
db.Offset(10).Find(&users1).Offset(-1).Find(&users2)
|
db.Offset(10).Find(&users1).Offset(-1).Find(&users2)
|
||||||
//// SELECT * FROM users OFFSET 10; (users1)
|
//// SELECT * FROM users OFFSET 10; (users1)
|
||||||
//// SELECT * FROM users; (users2)
|
//// SELECT * FROM users; (users2)
|
||||||
|
@ -565,29 +563,30 @@ db.Select("name, age").Find(&users)
|
||||||
|
|
||||||
## Callbacks
|
## Callbacks
|
||||||
|
|
||||||
Callback is a function defined to a struct, the function would be run when reflect a struct to database.
|
Callbacks are functions defined to struct's pointer, they would be run when save a struct to database.
|
||||||
If a function return error, gorm will prevent future operations and do rollback
|
If any callback return error, gorm will stop future operations and do rollback
|
||||||
|
|
||||||
Those callbacks are defined now:
|
Below callbacks are supported now:
|
||||||
|
|
||||||
`BeforeCreate`, `AfterCreate`
|
`BeforeCreate`, `AfterCreate`
|
||||||
`BeforeUpdate`, `AfterUpdate`
|
`BeforeUpdate`, `AfterUpdate`
|
||||||
`BeforeSave`, `AfterSave`
|
`BeforeSave`, `AfterSave`
|
||||||
`BeforeDelete`, `AfterDelete`
|
`BeforeDelete`, `AfterDelete`
|
||||||
|
|
||||||
|
For example:
|
||||||
|
|
||||||
```go
|
```go
|
||||||
// Won't update readonly user
|
|
||||||
func (u *User) BeforeUpdate() (err error) {
|
func (u *User) BeforeUpdate() (err error) {
|
||||||
if u.readonly() {
|
if u.readonly() {
|
||||||
err = errors.New("Read Only User")
|
err = errors.New("Read Only User!")
|
||||||
}
|
}
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
|
|
||||||
// If have more than 1000 users, will rollback the insertion
|
// Rollback the insertion if have more than 1000 users
|
||||||
func (u *User) AfterCreate() (err error) {
|
func (u *User) AfterCreate() (err error) {
|
||||||
if (u.Id > 1000) { // just an example, don't use Id to count users
|
if (u.Id > 1000) { // Just as example, don't use Id to count users!
|
||||||
err = errors.New("Only 1000 users allowed")
|
err = errors.New("Only 1000 users allowed!")
|
||||||
}
|
}
|
||||||
return
|
return
|
||||||
}
|
}
|
||||||
|
@ -596,26 +595,20 @@ func (u *User) AfterCreate() (err error) {
|
||||||
## Specify Table Name
|
## Specify Table Name
|
||||||
|
|
||||||
```go
|
```go
|
||||||
// When Create Table from struct
|
// Create `deleted_users` table with User's fields
|
||||||
db.Table("deleted_users").CreateTable(&User{})
|
db.Table("deleted_users").CreateTable(&User{})
|
||||||
|
|
||||||
// When Pluck
|
// Search from table `deleted_users`, and fill results to []User
|
||||||
db.Table("users").Pluck("age", &ages)
|
|
||||||
//// SELECT age FROM users;
|
|
||||||
|
|
||||||
// When Query
|
|
||||||
var deleted_users []User
|
var deleted_users []User
|
||||||
db.Table("deleted_users").Find(&deleted_users)
|
db.Table("deleted_users").Find(&deleted_users)
|
||||||
//// SELECT * FROM deleted_users;
|
//// SELECT * FROM deleted_users;
|
||||||
|
|
||||||
// When Delete
|
// Delete results from table `deleted_users` with search conditions
|
||||||
db.Table("deleted_users").Where("name = ?", "jinzhu").Delete()
|
db.Table("deleted_users").Where("name = ?", "jinzhu").Delete()
|
||||||
//// DELETE FROM deleted_users WHERE name = 'jinzhu';
|
//// DELETE FROM deleted_users WHERE name = 'jinzhu';
|
||||||
```
|
```
|
||||||
|
|
||||||
### Specify Table Name for Struct
|
### Specify Table Name for Struct permanently with TableName method
|
||||||
|
|
||||||
You are possible to specify table name for a struct by defining method TableName
|
|
||||||
|
|
||||||
```go
|
```go
|
||||||
type Cart struct {
|
type Cart struct {
|
||||||
|
@ -664,7 +657,7 @@ db.LogMode(true)
|
||||||
|
|
||||||
```go
|
```go
|
||||||
// Use your own logger
|
// Use your own logger
|
||||||
// Checkout gorm's default logger for how to format messages: https://github.com/jinzhu/gorm/blob/master/logger.go#files
|
// Refer gorm's default logger for how to format messages: https://github.com/jinzhu/gorm/blob/master/logger.go#files
|
||||||
db.SetLogger(log.New(os.Stdout, "\r\n", 0))
|
db.SetLogger(log.New(os.Stdout, "\r\n", 0))
|
||||||
|
|
||||||
// Disable log
|
// Disable log
|
||||||
|
@ -687,10 +680,12 @@ query := db.Where("name = ?", "jinzhu").First(&user)
|
||||||
query := db.First(&user).Limit(10).Find(&users)
|
query := db.First(&user).Limit(10).Find(&users)
|
||||||
//// query.Error keep the latest error happened
|
//// query.Error keep the latest error happened
|
||||||
//// query.Errors keep all errors happened
|
//// query.Errors keep all errors happened
|
||||||
//// If an error happened, gorm will stop do query, insert, update, delete
|
//// If an error happened, gorm will stop following operations
|
||||||
|
|
||||||
// I often use below code to do error handling in real applicatoins
|
// I often use some code like below to do error handling when writting applicatoins
|
||||||
err = db.Where("name = ?", "jinzhu").First(&user).Error
|
if err := db.Where("name = ?", "jinzhu").First(&user).Error; err != nil {
|
||||||
|
// ...
|
||||||
|
}
|
||||||
```
|
```
|
||||||
|
|
||||||
## Advanced Usage With Query Chain
|
## Advanced Usage With Query Chain
|
||||||
|
@ -700,28 +695,33 @@ Already excited about above usage? Let's see some magic!
|
||||||
```go
|
```go
|
||||||
db.First(&first_article).Count(&total_count).Limit(10).Find(&first_page_articles).Offset(10).Find(&second_page_articles)
|
db.First(&first_article).Count(&total_count).Limit(10).Find(&first_page_articles).Offset(10).Find(&second_page_articles)
|
||||||
//// SELECT * FROM articles LIMIT 1; (first_article)
|
//// SELECT * FROM articles LIMIT 1; (first_article)
|
||||||
//// SELECT count(*) FROM articles; (count)
|
//// SELECT count(*) FROM articles; (total_count)
|
||||||
//// SELECT * FROM articles LIMIT 10; (first_page_articles)
|
//// SELECT * FROM articles LIMIT 10; (first_page_articles)
|
||||||
//// SELECT * FROM articles LIMIT 10 OFFSET 10; (second_page_articles)
|
//// SELECT * FROM articles LIMIT 10 OFFSET 10; (second_page_articles)
|
||||||
|
|
||||||
|
|
||||||
|
// Mix where conditions with inline conditions
|
||||||
db.Where("created_at > ?", "2013-10-10").Find(&cancelled_orders, "state = ?", "cancelled").Find(&shipped_orders, "state = ?", "shipped")
|
db.Where("created_at > ?", "2013-10-10").Find(&cancelled_orders, "state = ?", "cancelled").Find(&shipped_orders, "state = ?", "shipped")
|
||||||
//// SELECT * FROM orders WHERE created_at > '2013/10/10' AND state = 'cancelled'; (cancelled_orders)
|
//// SELECT * FROM orders WHERE created_at > '2013/10/10' AND state = 'cancelled'; (cancelled_orders)
|
||||||
//// SELECT * FROM orders WHERE created_at > '2013/10/10' AND state = 'shipped'; (shipped_orders)
|
//// SELECT * FROM orders WHERE created_at > '2013/10/10' AND state = 'shipped'; (shipped_orders)
|
||||||
|
|
||||||
|
|
||||||
|
// Search with shared conditions from different tables
|
||||||
db.Where("product_name = ?", "fancy_product").Find(&orders).Find(&shopping_carts)
|
db.Where("product_name = ?", "fancy_product").Find(&orders).Find(&shopping_carts)
|
||||||
//// SELECT * FROM orders WHERE product_name = 'fancy_product'; (orders)
|
//// SELECT * FROM orders WHERE product_name = 'fancy_product'; (orders)
|
||||||
//// SELECT * FROM carts WHERE product_name = 'fancy_product'; (shopping_carts)
|
//// SELECT * FROM carts WHERE product_name = 'fancy_product'; (shopping_carts)
|
||||||
// Do you noticed the table is different?
|
|
||||||
|
|
||||||
db.Where("mail_type = ?", "TEXT").Find(&users1).Table("deleted_users").First(&user2)
|
|
||||||
|
// Search with shared conditions from different tables with specified table
|
||||||
|
db.Where("mail_type = ?", "TEXT").Find(&users1).Table("deleted_users").Find(&users2)
|
||||||
//// SELECT * FROM users WHERE mail_type = 'TEXT'; (users1)
|
//// SELECT * FROM users WHERE mail_type = 'TEXT'; (users1)
|
||||||
//// SELECT * FROM deleted_users WHERE mail_type = 'TEXT'; (users2)
|
//// SELECT * FROM deleted_users WHERE mail_type = 'TEXT'; (users2)
|
||||||
|
|
||||||
db.Where("email = ?", "x@example.org").Attrs(User{FromIp: "111.111.111.111"}).FirstOrCreate(&user)
|
|
||||||
//// SELECT * FROM users WHERE email = 'x@example.org';
|
|
||||||
//// INSERT INTO "users" (email,from_ip) VALUES ("x@example.org", "111.111.111.111") (if no record found)
|
|
||||||
|
|
||||||
// Open your mind, add more cool examples
|
// An example for how to use FirstOrCreate
|
||||||
|
db.Where("email = ?", "x@example.org").Attrs(User{RegisteredIp: "111.111.111.111"}).FirstOrCreate(&user)
|
||||||
|
//// SELECT * FROM users WHERE email = 'x@example.org';
|
||||||
|
//// INSERT INTO "users" (email,registered_ip) VALUES ("x@example.org", "111.111.111.111") // if no record found
|
||||||
```
|
```
|
||||||
|
|
||||||
## TODO
|
## TODO
|
||||||
|
|
Loading…
Reference in New Issue