Cloud computing has emerged as a paradigm for delivering Information Technology services over Internet. Services are provided according to a pricing model and meet requirements that are specified in Service Level Agreements (SLA). Recently, most of cloud providers include services for DataBase (DB) querying dedicated to run on MapReduce platform and a virtualized architecture. Classical resource allocation methods for query optimization need to be revised to handle the pricing models in cloud environnements. In this work, we propose a resource allocation method for the query optimization in the cloud based on Integer Linear-Programming (ILP). The proposed linear models can be implemented in any fast solver for ILP. The method is compared with some existing greedy algorithms. Experimental evaluation shows that the solution offers a good trade-off between the allocation quality and allocation cost.