drizzle-team/drizzle-orm · error · Error

Set operator error (union / intersect / except): selected fi

Error message

Set operator error (union / intersect / except): selected fields are not the same or are in a different order

What it means

Error "Set operator error (union / intersect / except): selected fields are not the same or are in a different order" thrown in drizzle-team/drizzle-orm.

Source

Thrown at drizzle-orm/src/gel-core/query-builders/select.ts:516

		rightSelection:
			| ((setOperators: GetGelSetOperators) => SetOperatorRightSelect<TValue, TResult>)
			| SetOperatorRightSelect<TValue, TResult>,
	) => GelSelectWithout<
		this,
		TDynamic,
		GelSetOperatorExcludedMethods,
		true
	> {
		return (rightSelection) => {
			const rightSelect = (typeof rightSelection === 'function'
				? rightSelection(getGelSetOperators())
				: rightSelection) as TypedQueryBuilder<
					any,
					TResult
				>;

			if (!haveSameKeys(this.getSelectedFields(), rightSelect.getSelectedFields())) {
				throw new Error(
					'Set operator error (union / intersect / except): selected fields are not the same or are in a different order',
				);
			}

			this.config.setOperators.push({ type, isAll, rightSelect });
			return this as any;
		};
	}

	/**
	 * Adds `union` set operator to the query.
	 *
	 * Calling this method will combine the result sets of the `select` statements and remove any duplicate rows that appear across them.
	 *
	 * See docs: {@link https://orm.drizzle.team/docs/set-operations#union}
	 *
	 * @example
	 *

View on GitHub (pinned to b7862528fd)

Solutions

1. Ensure both sides of the union/intersect/except select the same fields with the same names and in the same order.
2. Use explicit column selections (not select() with different shapes) on each branch of the set operator.

When it happens

Trigger: Combining queries with union/intersect/except on Gel where the selected fields differ in name, type, or order.

Common situations: Different column subsets on each branch; different select order; extra computed field on one side only.

AI-assisted analysis of drizzle-team/drizzle-orm@b7862528fd (2026-08-03). Data as JSON: /data/errors/88f2f0d03cd598a0.json. Report an issue: GitHub.