what means having no SQL code example

Example: no sql

TLDR: NoSQL databases (aka "not only SQL") are non tabular, and store data differently than relational tables.
NoSQL databases come in a variety of types based on their data model. The main types are document, key-value,
wide-column, and graph. They provide flexible schemas and scale easily with large amounts of data and high user loads.

Refer link for more : https://www.mongodb.com/nosql-explained