Abstract: The object of the research is ways to store master data in corporate information systems. Building systems for integrating heterogeneous data is one way to solve the problem of master data management. The paper discusses the storage system for structured data in various databases. Such systems are called heterogeneous systems. Heterogeneous systems usually arise in cases where nodes that already operate their own database systems will eventually integrate into a distributed system. The aim of the work is to create a storage system for heterogeneous data in databases of various types. To build the system, the methodology “divergent development” is used. An approach to improving the efficiency of managing heterogeneous data in corporate information systems based on the “divergent development” programming paradigm is proposed. Within this paradigm, a domain-specific query language for a heterogeneous database has been developed. The effectiveness of the data integration system created can be judged by the test results given in the article.