SQL
Tended:
Status: decay
SQL (Structured Query Language) enables users to interact with relational databases. Data is structured in tables. Each table has:
- ▪ 1 column for each field and
- ▪ 1 row for each record.
An SQL statement is composed of:
- ▪ an ordered list of clauses (example:
SELECT, FROM, WHERE, …), - ▪ each clause has its own syntax and
- ▪ each statement ends in '
;'.
Example:
result
SELECT class
FROM fleet;
The above query will return the class column values for all rows in the fleet table.
RDBMS
A Relational Database Management System enables a user to define, create, maintain and control access to the database. The system that will accept your SQL query to and return a result. Some of the most common RDBMSs are:
- ▪ Microsoft Azure SQL Database
- ▪ MySQL
- ▪ PostgreSQL (or Postgres)
- ▪ SQLite
Due to its popularity, all examples in this digital garden will be referring to Postgres.
