本文整理汇总了Golang中github.com/jmoiron/sqlx.DB.Begin方法的典型用法代码示例。如果您正苦于以下问题：Golang DB.Begin方法的具体用法？Golang DB.Begin怎么用？Golang DB.Begin使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类github.com/jmoiron/sqlx.DB的用法示例。
在下文中一共展示了DB.Begin方法的3个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Golang代码示例。
示例1: RemoveDatabase
func RemoveDatabase(db *sqlx.DB, database string) {
query := fmt.Sprintf(`DROP DATABASE IF EXISTS %s`, database)
tx, err := db.Begin()
if err != nil {
tx.Rollback()
log.Error(err)
}
stmt, err := tx.Prepare(query)
if err != nil {
log.Error(err)
}
if _, err := stmt.Exec(); err != nil {
log.Error(err)
}
tx.Commit()
}示例2: Migrate
// Migrate executes all necessary migrations in the specified database.
func (m Migrations) Migrate(db *sqlx.DB) error {
var initialized bool
for _, migration := range m {
if !initialized {
db.Exec("CREATE TABLE IF NOT EXISTS schema_migrations (id bigint PRIMARY KEY)")
initialized = true
}
tx, err := db.Begin()
if err != nil {
return err
}
if _, err := tx.Exec("LOCK TABLE schema_migrations IN ACCESS EXCLUSIVE MODE"); err != nil {
tx.Rollback()
return err
}
var tmp bool
if err := tx.QueryRow("SELECT true FROM schema_migrations WHERE id = $1", migration.ID).Scan(&tmp); err != sql.ErrNoRows {
tx.Rollback()
if err == nil {
continue
}
return err
}
for _, s := range migration.Stmts {
if _, err = tx.Exec(s); err != nil {
tx.Rollback()
return err
}
}
if _, err := tx.Exec("INSERT INTO schema_migrations (id) VALUES ($1)", migration.ID); err != nil {
tx.Rollback()
return err
}
if err := tx.Commit(); err != nil {
return err
}
}
return nil
}示例3: ExportBulk
// ExportBulk экспортирует данные из xml-файла в таблицу указанную в описании xml-структуры
func ExportBulk(schema func(tableName string) string, xmlObject interface{}, w *sync.WaitGroup, c chan string, db *sqlx.DB, format *string, logger *log.Logger) {
defer w.Done()
const dateformat = "2006-01-02"
objName := extractXMLObjectName(xmlObject)
fields := extractFeilds(xmlObject)
searchFileName := objName.tableName
objName.tableName = strings.TrimSuffix(objName.tableName, "_")
DropAndCreateTable(schema(objName.tableName), objName.tableName, db)
var format2 string
format2 = *format
fileName, err2 := SearchFile(searchFileName, format2)
if err2 != nil {
logger.Fatalln("Error searching file:", err2)
}
pathToFile := format2 + "/" + fileName
xmlFile, err := os.Open(pathToFile)
if err != nil {
logger.Fatalln("Error opening file:", err)
}
defer xmlFile.Close()
decoder := xml.NewDecoder(xmlFile)
var inElement string
total := 0
i := 0
txn, err := db.Begin()
if err != nil {
logger.Fatalln(err)
}
query := pq.CopyIn(objName.tableName, fields...)
stmt, err := txn.Prepare(query)
if err != nil {
logger.Fatalln(err)
}
for {
if i == 50000 {
i = 0
_, err = stmt.Exec()
if err != nil {
logger.Fatalln(err)
}
err = stmt.Close()
if err != nil {
logger.Fatalln(err)
}
err = txn.Commit()
if err != nil {
logger.Fatalln(err)
}
txn, err = db.Begin()
if err != nil {
logger.Fatalln(err)
}
stmt, err = txn.Prepare(query)
if err != nil {
logger.Fatalln(err)
}
}
t, _ := decoder.Token()
// Если достигли конца xml-файла
if t == nil {
if i > 0 {
_, err = stmt.Exec()
if err != nil {
logger.Fatalln(err)
}
err = stmt.Close()
if err != nil {
logger.Fatalln(err)
}
err = txn.Commit()
if err != nil {
logger.Fatalln(err)
}
}
//c <- helpers.PrintRowsAffected(elementName, total)
//.........这里部分代码省略.........