SQL

Traditional way of storing the data before the database

• Sequential Master update in a single file and sort timely for the faster update, done on magnetic data drives

• Random access data , stored in the disk drives and faster access but sorting not feasible , disks were easy to do update and read

• Structured query language came as a standard to read and interact with database from different vendors

• SQL is most powerful non procedural language

Structure of Database Sheet

Creating the SQL database standard

Interactive Learning

• https://sqlbolt.com/

Reference

• Anomaly Detection using simple SQL

• Speeding up SQL queries by orders of magnitude using UNION

• Practical SQL for Data Analysis

• HOW TO INTERPRET POSTGRESQL EXPLAIN ANALYZE OUTPUT

• Thinking in Events: From Databases to Distributed Collaboration Software

• Recursion in SQL