Cluster Explorer Guide

Working directly with a ClickHouse cluster

The Altinity Cloud Manager UI provides the Cluster Explorer, a panel that lets you run queries against your ClickHouse databases, work with database schemas, look at processes running inside the cluster, and use a number of useful DBA tools.

If you’re looking for help on a particular aspect of the Cluster Explorer, you can skip ahead to any of the tasks:

Panel buttons and menus

The top of every tab looks like this:

Menus and buttons in the Cluster Explorer

Figure 1 - Cluster Explorer menus and buttons

The functions of the buttons and menus are:

  • - The back button. Takes you back to the cluster view for this cluster.
  • CLUSTER menu - Clicking this menu displays a dropdown list of all of the clusters in this environment. Whatever you do in the Cluster Explorer will be done on the selected cluster.
    The Cluster menu
  • RUN DDLs ON CLUSTER - If selected, Distributed DDL Queries are run on the cluster.
  • NODE menu - Lets you select the scope of anything you do in the Cluster Explorer. For the maddie-byok cluster, the menu looks like this:
    Menus and buttons in the Cluster Explorer
    Selecting Any means everything you do will be executed on a single node selected by the load balancer. All executes everything on every node. Beyond those two choices, you can select a node from the list of all nodes in this cluster.
  • IMPORT DATASET - lets you import a sample dataset into your ClickHouse cluster. See Importing a dataset below.
  • - The refresh button. Refreshes the display, as you would expect.

The Query tab

When you open the Cluster Explorer, you’ll be on the Query tab:

Query Page

Figure 2 - The Query tab

The text area at the top of the panel lets you run SQL statements by clicking the EXECUTE button. (You can also keep your hands on the keyboard by typing Ctrl or CMD + Enter.)

When you execute a query, the results appear under the text area:

Query results

Beneath the text area are helpful notes with links to ClickHouse documentation and a couple of example queries.

Above the text area, the left and right arrows let you move through the queries you’ve executed. The button brings up the Select User dialog:

The Select User dialog

This lets you select the user (and their permissions) to run the query. The down arrow lets you choose from the users defined for this cluster. If your account has the necessary permissions, you can also click the link in Manage ClickHouse users here to go directly to the user management panel.

The Schema tab

The Schema tab lets you view the databases and tables in your cluster. You can then select a table and see its details.

The schema tab

Figure 3 - The Schema tab

You can click the Show system tables checkbox to see the system tables as well. All of the table names are links; click on a table name to see the Table Details dialog, which has four subtabs:

The Table Description tab

The Table Description tab has a table of the database’s properties. There are dozens of them, some of which are shown here:

Table description column

The Table Schema tab

The Table Schema tab displays the table’s schema as an SQL statement:

Table schema column

Click the Copy to Clipboard link to put the schema on the clipboard.

The Sample Rows tab

The Sample Rows tab shows randomly selected rows from the table:

Sample rows column

The Column Compression tab

Finally, the Column Compression tab shows the details of the columns in the table and how much they have been compressed:

Column compression column

The Workload tab

The Workload tab shows you what’s happening in the system now:

Workloads page

Figure 4 - The Workload tab

It has four subtabs:

The Running Queries tab

The Running Queries tab shows the details of all the currently running queries:

CUrrently running queries

If you select one or more queries, the button becomes active.

The Query Stats tab

The Replication Queue tab

The Mutations tab

The Processes view displays the currently running processes on a cluster or node.

To view the processes view:

  1. Select Explore from either the Clusters View or the Clusters Detail Page.

  2. Select Processes from the top tab.

  3. Select the following node options:

    Select node for query.
    1. Any: Any node selected from the Zookeeper parameters.
    2. All: Run the query against all nodes in the cluster.
    3. Node: Select a specific node to run the query against.

The following information is displayed:

  • Query ID: The ClickHouse ID of the query.
  • Query: The ClickHouse query that the process is running.
  • Time: The elapsed time of the process.
  • User: The ClickHouse user running the process.
  • Client Address: The address of the client submitting the process.
  • Action: Stop or restart a process.

The DBA Tools tab

DBA Tools page

Figure 5 - The DBA Tools tab

Importing a dataset

The Cluster Explorer makes it easy to import a sample dataset. When you click the IMPORT DATASET button, you’ll see this dialog:

Select a dataset to import

Select the dataset you want and click NEXT. Next you’ll be asked about the database schema:

Use the database schema

In this example, three tables will be created when you click IMPORT. You can expand each of the entries to look at the database schema and change engine parameters if you want.

Click IMPORT to import the data. Notice that even though there’s another step in the wizard, clicking the button in the lower right (as you normally would) starts the import immediately.