How to use database callback functions in Golang?
Using the database callback function in Golang can achieve: executing custom code after the specified database operation is completed. Add custom behavior through separate functions without writing additional code. Callback functions are available for insert, update, delete, and query operations. You must use the sql.Exec, sql.QueryRow, or sql.Query function to use the callback function.
#How to use database callback function in Golang?
In Golang, using database callback functions allows us to execute custom code after performing specific database operations. One of the benefits of this is that custom behavior can be easily added without writing a lot of extra code.
Here's how to use database callback function in Golang:
import ( "context" "database/sql" "fmt" "log" _ "github.com/go-sql-driver/mysql" ) func main() { // 连接到数据库 db, err := sql.Open("mysql", "user:password@tcp(localhost:3306)/database_name") if err != nil { log.Fatal(err) } // 创建一个回调函数,在插入操作后打印一条消息 callback := func(ctx context.Context, result sql.Result) error { affected, err := result.RowsAffected() if err != nil { return err } fmt.Printf("插入了 %d 行记录\n", affected) return nil } // 使用回调执行插入操作 result, err := db.Exec("INSERT INTO table_name (column1, column2) VALUES (?, ?)", "value1", "value2", callback) if err != nil { log.Fatal(err) } // 处理结果 // ... }
In this example, we create a callback function that prints a message after the insert operation. We then use this callback function when performing an insert operation.
In addition to insert operations, callback functions can also be used for other database operations, such as updates, deletes, and queries.
It is worth noting that the callback function can only be used when using the sql.Exec
, sql.QueryRow
or sql.Query
function. .
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