Unused subquery item

Reports columns, aliases, and other subquery items that are not referenced in the outer query expression.

Example (PostgreSQL):

CREATE TABLE for_subquery(id INT);
SELECT a, q FROM (SELECT 1 AS a, 10 AS b, 2 + 3 AS q, id
      FROM for_subquery) x;

We reference a and q aliases from a subquery. But the b alias and the id column are not referenced in the outer SELECT statement. Therefore, b and id are grayed out.

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

SqlUnusedSubqueryItemInspection

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | SQL

Availability

By default bundled with: CLion 2024.1, DataGrip 2024.1, DataSpell 2024.1, GoLand 2024.1, IntelliJ IDEA 2024.1, JetBrains Rider 2023.3, PhpStorm 2024.1, PyCharm 2024.1, Qodana for .NET 2023.3, Qodana for Go 2024.1, Qodana for JVM 2024.1, Qodana for PHP 2024.1, Qodana for Ruby 2024.1, RubyMine 2024.1,
Can be installed with plugin: Database Tools and SQL, 241.SNAPSHOT

Last modified: 18 June 2024