---
title: "Materialize v0.37"
date: 2022-12-21
released: true
patch: 3
---

## v0.37.0

* Add support for connecting to Confluent Schema Registry using an
  [SSH tunnel](/sql/create-connection/#ssh-tunnel) connection to an SSH bastion
  server.

* Add [`mz_internal.mz_cluster_replica_utilization`](/sql/system-catalog/mz_internal/#mz_cluster_replica_utilization)
  to the system catalog. This view allows you to monitor the resource utilization for
  all extant cluster replicas as a % of the total resource allocation:

  ```mzsql
  SELECT * FROM mz_internal.mz_cluster_replica_utilization;
  ```

  ```nofmt
    replica_id | process_id |     cpu_percent      |    memory_percent
   ------------+------------+----------------------+----------------------
    1          | 0          |            9.6629961 |   0.6772994995117188
    2          | 0          |  0.10735560000000001 |   0.3876686096191406
    3          | 0          |           46.8730398 |      0.7110595703125
  ```

  It's important to note that these tables are part of an unstable interface of
  Materialize (`mz_internal`), which means that their values may change at any
  time, and you should not rely on them for tasks like capacity planning for the
  time being.

* Add `mz_internal.mz_storage_host_metrics` and
  `mz_internal.mz_storage_host_sizes` to the system catalog. These objects
  respectively expose the last known CPU and RAM utilization statistics for all
  processes of all extant storage hosts, and a mapping of logical sizes
  (e.g. `xlarge`) to the number of processes, as well as CPU and memory
  allocations for each process.

  The concept of a storage host is not user-facing, and is intentionally
  undocumented. It refers to the physical resource allocation on which
  Materialize can schedule multiple sources and sinks behind the scenes.

* Rename system catalog objects to adhere to the naming conventions defined in
  the Materialize [SQL style guide](https://github.com/chaas/materialize/blob/main/doc/developer/style.md).
  The affected objects are:

  | Schema        | Old name           | New name           |
  | ------------- | ------------------ | --------------------- |
  | `mz_internal` | `mz_source_status` | `mz_source_statuses` |
  | `mz_internal` | `mz_sink_status`   | `mz_sink_statuses`   |

* Support `JSON` as an output format of [`EXPLAIN TIMESTAMP`](https://materialize.com/docs/sql/explain-timestamp/).

* Fix a bug where the `to_timestamp` function would truncate the fractional part
  of negative timestamps (i.e. prior to the Unix epoch: January 1st, 1970 at
  00:00:00 UTC) {{% gh 16610 %}}, and return an error instead of `NULL` when the
  timestamp is out of range. The new behavior matches PostgreSQL.

* **Private preview.** Add a [WebSocket API endpoint](/integrations/websocket-api/)
	which supports interactive SQL queries over WebSockets.

* Change the JSON serialization for rows emitted by the [HTTP API endpoint](/integrations/http-api/)
  to exactly match the JSON serialization used by `FORMAT JSON` Kafka sinks.
  Previously, the HTTP SQL endpoint serialized datums using slightly different
  rules.