Gen Update

Update single column

When updating a single column with Update, it needs to have any conditions or it will raise error ErrMissingWhereClause, for example:

u := query.User

// Update with conditions
u.WithContext(ctx).Where(u.Activate.Is(true)).Update(u.Name, "hello")
// UPDATE users SET name='hello', updated_at='2013-11-17 21:34:10' WHERE active=true;

// Update with conditions
u.WithContext(ctx).Where(u.Activate.Is(true)).Update(u.Age, u.Age.Add(1))
// or
u.WithContext(ctx).Where(u.Activate.Is(true)).UpdateSimple(u.Age.Add(1))
// UPDATE users SET age=age+1, updated_at='2013-11-17 21:34:10' WHERE active=true;

u.WithContext(ctx).Where(u.Activate.Is(true)).UpdateSimple(u.Age.Zero())
// UPDATE users SET age=0, updated_at='2013-11-17 21:34:10' WHERE active=true;

Updates multiple columns

Updates supports update with struct or map[string]interface{}, when updating with struct it will only update non-zero fields by default

u := query.User

// Update attributes with `map`
u.WithContext(ctx).Where(u.ID.Eq(111)).Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})
// UPDATE users SET name='hello', age=18, active=false, updated_at='2013-11-17 21:34:10' WHERE id=111;

// Update attributes with `struct`
u.WithContext(ctx).Where(u.ID.Eq(111)).Updates(model.User{Name: "hello", Age: 18, Active: false})
// UPDATE users SET name='hello', age=18, active=false, updated_at='2013-11-17 21:34:10' WHERE id=111;

// Update with expression
u.WithContext(ctx).Where(u.ID.Eq(111)).UpdateSimple(u.Age.Add(1), u.Number.Add(1))
// UPDATE users SET age=age+1,number=number+1, updated_at='2013-11-17 21:34:10' WHERE id=111;

u.WithContext(ctx).Where(u.Activate.Is(true)).UpdateSimple(u.Age.Value(17), u.Number.Zero(), u.Birthday.Null())
// UPDATE users SET age=17, number=0, birthday=NULL, updated_at='2013-11-17 21:34:10' WHERE active=true;

NOTE When update with struct, GEN will only update non-zero fields, you might want to use map to update attributes or use Select to specify fields to update

Update selected fields

If you want to update selected fields or ignore some fields when updating, you can use Select, Omit

u := query.User

// Select with Map
// User's ID is `111`:
u.WithContext(ctx).Select(u.Name).Where(u.ID.Eq(111)).Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})
// UPDATE users SET name='hello' WHERE id=111;

u.WithContext(ctx).Omit(u.Name).Where(u.ID.Eq(111)).Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})
// UPDATE users SET age=18, active=false, updated_at='2013-11-17 21:34:10' WHERE id=111;

result, err := u.WithContext(ctx).Where(u.ID.Eq(111)).Updates(map[string]interface{}{"name": "hello", "age": 18, "active": false})

result.RowsAffected // affect rows number
err                 // error

Update from SubQuery

Update a table by using SubQuery

u := query.User
c := query.Company

u.WithContext(ctx).Update(u.CompanyName, c.Select(c.Name).Where(c.ID.EqCol(u.CompanyID)))
// UPDATE "users" SET "company_name" = (SELECT name FROM companies WHERE companies.id = users.company_id);

u.WithContext(ctx).Where(u.Name.Eq("modi")).Update(u.CompanyName, c.Select(c.Name).Where(c.ID.EqCol(u.CompanyID)))

Update multiple columns from SubQuery

Update multiple columns by using SubQuery (for MySQL):

u := query.User
c := query.Company

ua := u.As("u")
ca := u.As("c")

ua.WithContext(ctx).UpdateFrom(ca.WithContext(ctx).Select(c.ID, c.Address, c.Phone).Where(c.ID.Gt(100))).
Where(ua.CompanyID.EqCol(ca.ID)).
UpdateSimple(
  ua.Address.SetCol(ca.Address),
  ua.Phone.SetCol(ca.Phone),
)
// UPDATE `users` AS `u`,(
//   SELECT `company`.`id`,`company`.`address`,`company`.`phone`
//   FROM `company` WHERE `company`.`id` > 100 AND `company`.`deleted_at` IS NULL
// ) AS `c`
// SET `u`.`address`=`c`.`address`,`c`.`phone`=`c`.`phone`,`updated_at`='2021-11-11 11:11:11.111'
// WHERE `u`.`company_id` = `c`.`id`