我目前正在努力(第二天)找到进行多项查询的最佳方式,并且想知道你是否知道解决方案。
我有一个开放的* sql.DB连接,名为 myDb 并使用 go-sql-driver
func TruncateGalleryImport() error {
s := make([]string, 0)
s = append(s, "TRUNCATE TABLE add_map")
s = append(s, "TRUNCATE TABLE album")
s = append(s, "TRUNCATE TABLE album_permission")
s = append(s, "TRUNCATE TABLE album_view")
s = append(s, "TRUNCATE TABLE album_watch")
s = append(s, "TRUNCATE TABLE media")
s = append(s, "TRUNCATE TABLE media_user_view")
s = append(s, "TRUNCATE TABLE media_view")
s = append(s, "TRUNCATE TABLE media_watch")
s = append(s, "TRUNCATE TABLE private_map")
s = append(s, "TRUNCATE TABLE attachment")
s = append(s, "TRUNCATE TABLE attachment_data")
for _, q := range s {
_, err := myDb.Exec(q)
if err != nil {
return err
}
}
return nil
}
是否可以仅使用一个事务将所有上述查询一起提交?
干杯
答案 0 :(得分:3)
使用事务,如下所示(请参阅代码中的注释):
func TruncateGalleryImport() error {
s := make([]string, 0)
s = append(s, "TRUNCATE TABLE add_map")
s = append(s, "TRUNCATE TABLE album")
s = append(s, "TRUNCATE TABLE album_permission")
s = append(s, "TRUNCATE TABLE album_view")
s = append(s, "TRUNCATE TABLE album_watch")
s = append(s, "TRUNCATE TABLE media")
s = append(s, "TRUNCATE TABLE media_user_view")
s = append(s, "TRUNCATE TABLE media_view")
s = append(s, "TRUNCATE TABLE media_watch")
s = append(s, "TRUNCATE TABLE private_map")
s = append(s, "TRUNCATE TABLE attachment")
s = append(s, "TRUNCATE TABLE attachment_data")
// Get new Transaction. See http://golang.org/pkg/database/sql/#DB.Begin
txn, err := myDb.Begin()
if err != nil {
return err
}
defer func() {
// Rollback the transaction after the function returns.
// If the transaction was already commited, this will do nothing.
_ = txn.Rollback()
}()
for _, q := range s {
// Execute the query in the transaction.
_, err := txn.Exec(q)
if err != nil {
return err
}
}
// Commit the transaction.
return txn.Commit()
}
答案 1 :(得分:2)
您可以使用包装函数来执行提交/回滚逻辑,甚至可以使用字符串匹配扩展错误处理。
// RDBTransaction is a function which abstracts a sql transaction
// into a function with an isolation level (isolvl) parameter.
// the following integers represent the available isolation levels (isolvl)
// 1: SERIALIZABLE
// 2: REPEATABLE READ
// 3: READ COMMITTED
// 4: READ UNCOMMITTED
func RDBTransaction(db *sql.DB, isolvl int, fn func(*sql.Tx) error) (err error) {
var tx *sql.Tx
tx, err = db.Begin()
if err != nil {
return err
}
// transaction isolation level setting
switch isolvl {
case 1:
_, err = tx.Exec(`set transaction isolation level serializable`)
case 2:
_, err = tx.Exec(`set transaction isolation level repeatable read`)
case 3:
_, err = tx.Exec(`set transaction isolation level read committed`)
case 4:
_, err = tx.Exec(`set transaction isolation level read uncommitted`)
default:
_, err = tx.Exec(`set transaction isolation level serializable`)
}
if err != nil {
return err
}
// catch all, commit/rollback
defer func() {
if err != nil {
tx.Rollback()
return
}
err = tx.Commit()
}()
// run transaction
err = fn(tx)
return err
}