Update [PostgreSQL MySQL]
API
For the full list of supported methods, see API referenceopen in new window.
db.NewUpdate().
With("cte_name", subquery).
Model(&strct).
Model(&slice).
Model(&map). // only map[string]interface{}
Column("col1", "col2"). // list of columns to insert
ExcludeColumn("col1"). // all columns except col1
ExcludeColumn("*"). // exclude all columns
Table("table1", "table2"). // quotes table names
TableExpr("table1 AS t1"). // arbitrary unsafe expression
TableExpr("(?) AS alias", subquery).
ModelTableExpr("table1 AS t1"). // overrides model table name
Value("col1", "expr1", arg1, arg2). // overrides column value
// Generates `SET col1 = 'value1'`
Set("col1 = ?", "value1").
SetColumn("col1", "?", "value1").
WherePK(). // where using primary keys
Where("id = ?", 123).
Where("name LIKE ?", "my%").
Where("? = 123", bun.Ident("id")).
Where("id IN (?)", bun.In([]int64{1, 2, 3})).
Where("id IN (?)", subquery).
Where("FALSE").WhereOr("TRUE").
WhereGroup(" AND ", func(q *bun.SelectQuery) *bun.SelectQuery {
return q.WhereOr("id = 1").
WhereOr("id = 2")
}).
Returning("*").
Returning("col1, col2").
Returning("NULL"). // don't return anything
Exec(ctx)
Example
To update a row, define a model and use UpdateQueryopen in new window:
book := &Book{ID: 123, Title: "hello"}
res, err := db.NewUpdate().Model(book).WherePK().Exec(ctx)
To update a single column:
book.Title = "hello"
res, err := db.NewUpdate().
Model(book).
Column("title").
Where("id = ?", 123).
Exec(ctx)
UPDATE books SET title = 'my title' WHERE id = 1
Alternatively:
res, err := db.NewUpdate().
Model(book).
Set("title = ?", "hello").
Where("id = ?", 123).
Exec(ctx)
Bulk-update
To bulk-update books, you can use a CTE:
values := db.NewValues([]*Book{book1, book2})
res, err := db.NewUpdate().
With("_data", values).
Model((*Book)(nil)).
TableExpr("_data").
Set("title = _data.title").
Set("text = _data.text").
Where("book.id = _data.id").
Exec(ctx)
WITH _data (id, title, text) AS (
VALUES
(1, 'title1', 'text1'),
(2, 'title2', 'text2')
)
UPDATE books AS book
SET title = _data.title, text = _data.text
FROM _data
WHERE book.id = _data.id
Alternatively, you can use Bulk
helper which creates a CTE for you:
res, err := db.NewUpdate().
Model(&books).
Column("title", "text").
Bulk().
Exec(ctx)
Maps
To update using a map[string]interface{}
:
value := map[string]interface{}{
"title": "title1",
"text": "text1",
}
res, err := db.NewUpdate().
Model(&value).
TableExpr("books").
Where("id = ?", 1).
Exec(ctx)
UPDATE books
SET title = 'title1', text = 'text2'
WHERE id = 1
Omit zero values
You can also tell Bun to omit zero struct fields, for example, the following query does not update email
column because it contains an empty value:
type User struct {
ID int64
Name string
Email string
}
res, err := db.NewUpdate().
Model(&User{ID: 1, Name: "John Doe"}).
OmitZero().
WherePK().
Exec(ctx)
UPDATE users
SET name = "John Doe"
WHERE id = 1
FQN
Multi-table updates differ in PostgreSQL and MySQL:
-- PostgreSQL
UPDATE dest FROM src SET col1 = src.col1 WHERE dest.id = src.id
-- MySQL
UPDATE dest, src SET dest.col1 = src.col1 WHERE dest.id = src.id
Bun helps you write queries for both databases by providing SetColumn
method:
res, err := db.NewUpdate().
Table("dest", "src").
SetColumn("col1", "src.col1").
Where("dest.id = src.id").
Exec(ctx)
If you have a slice of models to update, use Bulk
method:
res, err := db.NewUpdate().
Model(&models).
Column("col1").
Bulk().
Exec(ctx)