The relational database data model is simple, and they are all single-level two-dimensional tables with clear rows and columns. It is relatively simple to use SQL. In MongoDB, there is a multi-level nested structure. The attribute fields appear arbitrarily, and it is not easy to describe which field information of…

One of the biggest differences between SQL and NoSQL databases is JOIN. Although MongoDB introduced $lookup as a supplement to the use of relational data in NoSQL databases, even if it is a simple two-table association, $lookup needs to be replaced with complex aggregate queries. The actual application environment is…

Java SE 8 introduces the Stream API. This new way of writing code is quite different from the previous way of processing collections. With only a filter, map, reduce, and iterate, you can write concise and expressive data processing queries. For this reason, many programmers try to replace SQL with…

Jerry Cruise

Products and resources that simplify hard data processing tasks. If you have any questions, send me a message. https://www.linkedin.com/in/witness998

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