n8n-io/n8n · error · TypeORMError

Function parameter isn't supported in the parameters. Please

Error message

Function parameter isn't supported in the parameters. Please check "${key}" parameter.

What it means

QueryBuilder.setParameter() throws TypeORMError when the value argument is a function. SQL parameter values must be serializable scalars/objects (string, number, boolean, Date, buffer, array); a function cannot be bound to a prepared-statement parameter and would produce nonsensical SQL. The check is a hard guard before storing the value in expressionMap.parameters.

Source

Thrown at packages/@n8n/typeorm/src/query-builder/QueryBuilder.ts:357

			return !!entityMetadata.findRelationWithPropertyPath(relation);
		});
	}

	/**
	 * Check the existence of a parameter for this query builder.
	 */
	hasParameter(key: string): boolean {
		return this.parentQueryBuilder?.hasParameter(key) || key in this.expressionMap.parameters;
	}

	/**
	 * Sets parameter name and its value.
	 *
	 * The key for this parameter may contain numbers, letters, underscores, or periods.
	 */
	setParameter(key: string, value: any): this {
		if (typeof value === 'function') {
			throw new TypeORMError(
				`Function parameter isn't supported in the parameters. Please check "${key}" parameter.`,
			);
		}

		if (!key.match(/^([A-Za-z0-9_.]+)$/)) {
			throw new TypeORMError(
				'QueryBuilder parameter keys may only contain numbers, letters, underscores, or periods.',
			);
		}

		if (this.parentQueryBuilder) {
			this.parentQueryBuilder.setParameter(key, value);
		}

		this.expressionMap.parameters[key] = value;
		return this;
	}

View on GitHub (pinned to 5ac6606e81)

Solutions

1. Invoke functions before passing: Date.now() not Date.now.
2. Coerce/serialize the value to a primitive, Date, or array before setParameter.
3. If you need dynamic SQL fragments, use string interpolation in the where clause with proper escaping, not a parameter.
4. Audit setParameters object values for function members.

Example fix

// before
qb.andWhere('u.createdAt > :now', {})
  .setParameter('now', Date.now); // function, throws

// after
qb.andWhere('u.createdAt > :now', {})
  .setParameter('now', Date.now());

function isBindableParam(v: unknown): boolean {
  return v == null || ['string','number','boolean','bigint'].includes(typeof v) || v instanceof Date || Buffer.isBuffer(v) || Array.isArray(v);
}
if (!isBindableParam(value)) throw new Error('parameter value must be a scalar/Date/Buffer/array, got function');

function isBindableValue(v: unknown): v is string | number | boolean | Date | Buffer | unknown[] | null {
  return v == null || typeof v === 'string' || typeof v === 'number' || typeof v === 'boolean' || v instanceof Date || Buffer.isBuffer(v) || Array.isArray(v);
}

When it happens

Trigger: Calling .setParameter('key', someFunction) or .setParameters({ key: fn }). Also when passing a value that is unexpectedly a function due to a missing invocation, e.g. .setParameter('now', Date.now) instead of Date.now().

Common situations: Forgetting to invoke a function (Date.now vs Date.now()). Passing a comparator or callback by mistake. Dynamic parameter building that accidentally includes a function from user input.

Related errors

• QueryBuilder parameter keys may only contain numbers, letter
• Parameter ${key} must be a string
• Cannot perform insert query because values are not defined.
• cte.options.columnNames length (${cte.options.columnNames.le
• Provided "limit" value is not a number. Please provide a num

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/c1a69d64a9e07f3d. Report an issue: GitHub.