SQL
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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 &
- ▪ 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 &
- ▪ each statement ends in '
;
'.
Example:
/query.sql
result
SELECT classFROM 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 & control access to the database. The system that will accept your SQL query to & 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.

Resources
Documentation | |
---|---|
SQL - Performance | |
Examples | |
SQL - Create / Read data | |
SQL - Update / Delete data | |
Misc. | |
SQL Police Department | An SQL game |