未约定履行期限的合同在理论和实践中都会存在。相关司法解释认为此种合同的诉讼时效应以债权人要求的合理宽限期届满之日起算,实际上无形的扩张了债权人的权利。结合《民法通则》关于一般情况下诉讼时效起算的规定,“合同生效之日”即为权利人知道或者应当知道权利被侵害之日,诉讼时效由此起算。 Contracts that do not agree on the deadline will exist both in theory and in practice. Relevant judicial interpretations argue that the litigating effect of such a contract starts from the date of the expiration of a reasonable grace period required by the creditors, in effect extending the creditor’s rights invisibly. Combined with the General Provisions of Civil Law on the general provisions of the statute of limitation, “the effective date of the contract ” is the right to know or should know the rights infringed the date of the commencement of the proceedings.