SQL 101

When I learn something, I like to summarize the structure of the knowledge so that I can focus on the essential instead of falling deep into the rabbit hole.

1. What is SQL?

SQL is a language to operate databases; it includes database creation, deletion, and query. SQL is an ANSI standard language but there are many version of SQL language (like English, there British English and American English, while they are the same language)

2. What is RDBMS?

RDBMS (relational database management system) is a database management system based on the…