Presto Console – SQL Client on Web UI

The Presto command line interface (CLI) is one of the de facto tools for interacting with the Presto SQL engine. To use it, you need to download the jar file and a Java runtime. You can find detailed information here. You’re probably wondering: “Is there an easier way to run SQL queries?”. The answer is “YES”! Thanks to the Bhuma team for contributing the presto-js-client to the Presto community. The presto-js-client enables the capability to communicate with the Presto SQL engine using JavaScript, one of the trending programming languages. To extend the benefits of the presto-js-client even further, the Presto Console was introduced to the Presto UI in version 0.286. This allows you to execute SQL queries directly from a web browser. Without further ado, let’s explore the features provided by the Presto Console.

First thing first, open the Presto web UI on a browser and click on the SQL Client at the top banner to view the UX of the Presto Console:

The UX of the Presto Console is quite simple and self-explanatory. There is a dismissible message box mentioning how to set up the access controls and authorization policies to manage accessibility to the Presto Console. Please follow the documentation to set up access controls and authorization policies based on your requirements. You can close the message box by clicking the cross sign in the upper right corner. The main UX is comprised of two dropdown lists, Catalog and Schema, a Run button, and a SQL input text area.

Use the Catalog and Schema drop-down lists to select the default catalog and schema for the SQL query. When you select a catalog, the Schema drop-down list will show you the available schemas. Once the catalog and schema are specified, they become the default values for the SQL query. To conserve the memory footprint used by the Presto Console, a SELECT query will be limited to 100 returned records by appending limit 100 to the end of your SQL when you click the Run button. The query results are presented in a table view below the SQL input. Here is an example of running a TPCH query:

Use the navigation bar at the bottom of the table to view the results. If you are interested in the query plan for the SQL query, you can click the link at the top of the table to get detailed information.

In version 0.287, support for session properties has been added to the Presto Console. A new tab called “Session Properties” has been created to display all session properties and to allow for modification if necessary. Simply click on the session property and remember to hit the Enter key after typing in the new value. The session properties you changed will be highlighted in a different color, like this:

Once you are done with the session properties, you can switch back to the SQL tab to type in and run the SQL query as usual.

That’s all about the Presto Console. Hope you like it and find it useful. If you’d like to see any features in the Presto Console, feel free to open an issue at the prestodb/presto repository.