# Select API Quickstart Guide [![Slack](https://slack.min.io/slack?type=svg)](https://slack.min.io)

Traditional retrieval of objects is always as whole entities, i.e GetObject for a 5 GiB object, will always return 5 GiB of data. S3 Select API allows us to retrieve a subset of data by using simple SQL expressions. By using Select API to retrieve only the data needed by the application, drastic performance improvements can be achieved.

                    final GetObjectArgs args = GetObjectArgs.builder().bucket(bucketName).object(path).build();
                    try (InputStream contentStream = new BufferedInputStream(minioClient.getObject(args))) {
                        responseData.setResponseBody(InputStreamUtil.getBytes(contentStream));
                    } catch (final Exception e) {
                        logger.warn("I/O Exception.", e);

            }
            try {
                final GetObjectArgs args = GetObjectArgs.builder().bucket(bucketName).object(objectName).build();
                return minioClient.getObject(args);
            } catch (InvalidKeyException | ErrorResponseException | IllegalArgumentException | InsufficientDataException | InternalException

		return 0, nil, errors.New("bucket name cannot be empty")
	}

	clnt, err := driver.getMinIOClient(ctx)
	if err != nil {
		return 0, nil, err
	}

	opts := minio.GetObjectOptions{}
	obj, err := clnt.GetObject(context.Background(), bucket, object, opts)
	if err != nil {
		return 0, nil, err
	}
	defer func() {
		if err != nil && obj != nil {
			obj.Close()
		}
	}()

	// GCS storage decompresses a gzipped object by default and returns the data.
	// Refer to https://cloud.google.com/storage/docs/transcoding#decompressive_transcoding
	// Need to set `Accept-Encoding` header to `gzip` when issuing a GetObject call, to be able
	// to download the object in compressed state.
	// Calling ReadCompressed with true accomplishes that.
	object := gcs.client.Bucket(gcs.Bucket).Object(gcs.getDest(key)).ReadCompressed(true)

			continue
		}

		var forwardTo string
		// If we resume to the same bucket, forward to last known item.
		b := tracker.getBucket()
		if b == bucket {
			forwardTo = tracker.getObject()
		}
		if b != "" {
			// Reset to where last bucket ended if resuming.
			tracker.resume()
		}
		tracker.setObject("")
		tracker.setBucket(bucket)
		// Heal current bucket again in case if it is failed

			HandlerFunc(s3APIMiddleware(api.GetObjectLegalHoldHandler)).
			Queries("legal-hold", "")
		// GetObject with lambda ARNs
		router.Methods(http.MethodGet).Path("/{object:.+}").
			HandlerFunc(s3APIMiddleware(api.GetObjectLambdaHandler, traceHdrsS3HFlag)).
			Queries("lambdaArn", "{lambdaArn:.*}")
		// GetObject
		router.Methods(http.MethodGet).Path("/{object:.+}").

	policy := "mypolicy"
	policyBytes := []byte(`{
 "Version": "2012-10-17",
 "Statement": [
  {
   "Effect": "Allow",
   "Action": [
    "s3:PutObject",
    "s3:GetObject",
    "s3:ListBucket"
   ],
   "Resource": [
    "arn:aws:s3:::BUCKET/*"
   ]
  }
 ]
}`)

	err := s.adm.AddCannedPolicy(ctx, policy, policyBytes)
	if err != nil {

	if bucket == "" {
		return nil, errors.New("bucket name cannot be empty")
	}

	clnt, err := f.getMinIOClient()
	if err != nil {
		return nil, err
	}

	obj, err := clnt.GetObject(context.Background(), bucket, object, minio.GetObjectOptions{})
	if err != nil {
		return nil, err
	}

	_, err = obj.Stat()
	if err != nil {
		return nil, err
	}

	return obj, nil
}

				return
			}
			for {
				if objCountPerThread[i] == j {
					j = 0
				}
				tmpObjName := pathJoin(objNamePrefix, fmt.Sprintf("%d/%d", i, j))
				t := time.Now()

				r, _, _, err := c.GetObject(downloadsCtx, opts.bucketName, tmpObjName, gopts)
				if err != nil {
					errResp, ok := err.(minio.ErrorResponse)
					if ok && errResp.StatusCode == http.StatusNotFound {
						continue
					}