SQL Server Execution Plans, Third Edition, by Grant Fritchey

SQL Server 2019 preview builds on previous releases to grow SQL Server as a platform that gives you choices of development languages, data types, on-premises or cloud, and operating systems. This article summarizes what is new for SQL Server 2019. 

sqlfmt is an online SQL formatter. It is pronounced sequel fumpt. Its purpose is to beautifully format SQL statements.  

First public preview of SQL Server 2019 : CTP 2.0 

The free SQL Server 2019 preview download is out 

SQL Style Guide 

A meme is an idea, behavior, or style that spreads from person to person within a culture—often with the aim of conveying a particular phenomenon, theme, or meaning represented by the meme.

This is an interactive book which aims to be the best place on the internet for learning SQL.