Abstract: The article is devoted to creating a quick method of comparing a huge amount of data tables in relational database management systems. Creating an effective method for comparing relational systems is really relevant today. The study of existing solutions was conducted. The algorithm in this article was created using the probabilistic data structure «Countable Bloom filter» and the Monte Carlo Method. The proposed solution is unique in its direction, as it uses the least amount of temporary resources. A probabilistic model of the created algorithm is constructed, this algorithm can be used for parallelization.