The standards for granting mandamus relief are well established. Mandamus is an extraordinary remedy available only in limited circumstances to correct a clear abuse of discretion or the violation of a duty imposed by law when the relator has no adequate remedy at law. Republican Party of Tex. v. Dietz, 940 S.W.2d 86, 88 (Tex. 1997); Walker v. Packer, 827 S.W.2d 833, 839-44 (Tex.1992); In re Cobos, 994 S.W.2d 313, 315 (Tex. App.-Corpus Christi 1999, no pet.). An appellate remedy is generally adequate even though it involves delay and more expense than obtaining an extraordinary writ. In re Masonite Corp., 997 S.W.2d 194, 197 (Tex. 1999). Mandamus is appropriate only in those rare occasions where exceptional circumstances render the appellate remedy inadequate. Id. A relator complaining the trial court incorrectly decided an issue of law must show the trial court failed to analyze or apply the law correctly because the trial court's erroneous interpretation of the law constitutes a clear abuse of discretion. Huie v. DeShazo, 922 S.W.2d 920, 927 (Tex. 1996); Walker, 827 S.W.2d at 840.