In recent years, systems become more complex due to massive growth and variety of data which stored in different formats (structured and unstructured). In many cases the organizations need to use both SQL and NoSQL databases to store their data and get the advantages of both systems. A big challenge for organizations is how to integrate these data and retrieve it in a uniform format. The difficulty of integration is not only because the heterogeneity of query language and the data format but also the heterogeneity of semantic and structure. Although many researches were done to overcome these challenges, it introduced a specific solution for a special case or limited feature rather than a general model. This paper introduces a standard solution to integrate SQL with NoSQL databases and retrieve data from them in a unified form. The proposed model allows developers to write and execute queries against different data sources easily at the same time. This model solves the problems of heterogeneous data integration along three diagonal structure, semantic, and syntax heterogeneity. A web-based application is developed to ensure the usefulness of the proposed solution.