Patch Time Series Entries

• Patching multiple time series entries (append or delete entries) can be performed via the Session
  using session.Advanced.Defer, as described below.

  • You can handle a single document at a time.
  • The patching action is defined by the provided JavaScript.

• Patching time series entries can also be done directly on the Store via Operations,
  where multiple documents can be handled at a time. Learn more in Patching time series operations.

• In this page:

  • Usage
  • Patching examples
    • Append multiple entries
    • Delete multiple entries
  • Syntax

Usage

• Open a session
• Construct a PatchCommandData instance and pass it the following:
  • The document ID that contains the time series
  • The document change vector (or null)
  • A PatchRequest instance with a JavaScript that appends or removes time series entries
• Call session.Advanced.Defer and pass it the PatchCommandData command.
  Note that you can call Defer multiple times prior to calling SaveChanges.
• Call session.SaveChanges().
  All patch requests added via Defer will be sent to the server for execution when SaveChanges is called.

Patching examples

Append multiple entries:

In this example, we append 100 time series entries with random heart rate values to a document.

var baseline = DateTime.Today;

// Create arrays of timestamps and random values to patch
List<double> values = new List<double>();
List<DateTime> timeStamps = new List<DateTime>();

for (var i = 0; i < 100; i++)
{
  values.Add(68 + Math.Round(19 * new Random().NextDouble()));
  timeStamps.Add(baseline.AddSeconds(i));
}

session.Advanced.Defer(new PatchCommandData("users/1-A", null,
  new PatchRequest
  {
      Script = @"
          var i = 0;
          for(i = 0; i < $values.length; i++)
          {
              timeseries(id(this), $timeseries)
              .append (
                new Date($timeStamps[i]), 
                $values[i], 
                $tag);
          }",

      Values =
      {
          { "timeseries", "HeartRates" },
          { "timeStamps", timeStamps},
          { "values", values },
          { "tag", "watches/fitbit" }
      }
  }, null));

session.SaveChanges();

Delete multiple entries:

In this example, we remove a range of 50 time series entries from a document.

// Delete time-series entries
session.Advanced.Defer(new PatchCommandData("users/1-A", null,
  new PatchRequest
  {
      Script = @"timeseries(this, $timeseries)
               .delete(
                  $from, 
                  $to
                );",
      Values =
      {
          { "timeseries", "HeartRates" },
          { "from", baseline.AddSeconds(0) },
          { "to", baseline.AddSeconds(49) }
      }
  }, null));

session.SaveChanges();

Syntax

PatchCommandData

public PatchCommandData(string id, string changeVector,
  PatchRequest patch, PatchRequest patchIfMissing)

Learn more about PatchCommandData here. PatchRequest

public class PatchRequest
{
  // The patching script     
  public string Script { get; set; }
  
  // Values for the parameters used by the patching script
  public Dictionary<string, object> Values { get; set; }
}

Learn more about PatchRequest here.