Here are some references I’ve found particularly useful when developing or debugging SQL code. When trying something new, I like to have a user’s guide open at my left elbow, a language reference guide open at my right elbow, and a cup of dark coffee steaming above the keyboard. When debugging, I like to have a debugger reference on the left, and a large unloaded revolver at my right. (The bugs find the revolver intimidating, and I find that snapping sound more rewarding than admitting my programming errors.)
SQL Reference Guides
These provide encyclopedic reference on the details of function and syntax.
MariaDB SQL Language Reference:
PostgreSQL Language Reference:
MySQL Language Reference:
T-SQL Language Reference:
The better organized on-line tutorials easily serve as user’s guides.
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