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.