Bulk upsert of data


    The article is being updated.

    YDB supports bulk upsert of many records without atomicity guarantees. The upsert process is split into multiple independent parallel transactions, each covering a single partition. For that reason, this approach is more effective than using YQL. If successful, the BulkUpsert method guarantees inserting all the data transmitted by the query.

    Below are code examples showing the YDB SDK built-in tools for bulk upsert:

    package main
    import (
    func main() {
      ctx, cancel := context.WithCancel(context.Background())
      defer cancel()
      db, err := ydb.Open(ctx,
      if err != nil {
      defer db.Close(ctx)
      type logMessage struct {
        App       string
        Host      string
        Timestamp time.Time
        HTTPCode  uint32
        Message   string
      // prepare native go data
      const batchSize = 10000
      logs := make([]logMessage, 0, batchSize)
      for i := 0; i < batchSize; i++ {
        message := logMessage{
          App:       fmt.Sprintf("App_%d", i/256),
          Host:      fmt.Sprintf("192.168.0.%d", i%256),
          Timestamp: time.Now().Add(time.Millisecond * time.Duration(i%1000)),
          HTTPCode:  200,
        if i%2 == 0 {
          message.Message = "GET / HTTP/1.1"
        } else {
          message.Message = "GET /images/logo.png HTTP/1.1"
        logs = append(logs, message)
      // execute bulk upsert with native ydb data
      err = db.Table().Do( // Do retry operation on errors with best effort
        ctx, // context manage exiting from Do
        func(ctx context.Context, s table.Session) (err error) { // retry operation
          rows := make([]types.Value, 0, len(logs))
          for _, msg := range logs {
            rows = append(rows, types.StructValue(
              types.StructFieldValue("App", types.UTF8Value(msg.App)),
              types.StructFieldValue("Host", types.UTF8Value(msg.Host)),
              types.StructFieldValue("Timestamp", types.TimestampValueFromTime(msg.Timestamp)),
              types.StructFieldValue("HTTPCode", types.Uint32Value(msg.HTTPCode)),
              types.StructFieldValue("Message", types.UTF8Value(msg.Message)),
          return s.BulkUpsert(ctx, "/local/bulk_upsert_example", types.ListValue(rows...))
      if err != nil {
        fmt.Printf("unexpected error: %v", err)

    The implementation of YDB database/sql doesn't support bulk nontransactional upsert of data.
    For bulk upsert, use transactional upsert.