Multidimensional Expressions (MDX) is a query language for online analytical processing (OLAP) using a database management system. Much like SQL, it is a query language for OLAP cubes. It is also a calculation language, with syntax similar to spreadsheet formulas MDX is an extension to Markdown that lets you include JSX in Markdown documents. MDX makes it possible to include React components in your Gatsby blog posts and pages. Markdown defines a plain text syntax for HTML elements such as h1, strong, and a, but still supports inline HTML. Many developers choose to use 4-space or 2-space indentation. In MDX, each nested statement (e.g., a statement following a '{' brace) should be indented exactly once more than the previous line's indentation.)