Is there another action pending between the same parties on the same cause of action?

[62 Cal.App.3d 966] The trial court erred, therefore, in sustaining the demurrer on the ground that there is another action pending between the same parties on the same cause of action. The sustaining of the demurrer on this ground alone does not, however, preclude our determining whether the demurrer should have been sustained on the ground that the complaint does not state cause of action. The trial court's ruling should be upheld if it can be sustained on any of the grounds upon which the demurrer is based. (Elton v. County of Orange, 3 Cal.App.3d 1053, 1058--1059, 84 Cal.Rptr. 27.)