Christophe Limpalair
Co-Founder of Cybr, and Course Author
What is SQL?
- SQL is a language designed for communicating with databases that store data
- It allows us to read, write, and edit our data, and it also allows us to configure or manage the database engine
What is SQL?
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Database engines have tables that provide access to the database's metadata
Different engines use different names:
| Engine | Table name |
|---|---|
| SQLite | sqlite_master |
| MySQL | information_schema |
| PostgreSQL | information_schema |
| Oracle | dba_tables |
The sqlite_master table looks like this:
| Column Name | Description |
|---|---|
| type | The type of database object such as table, index, trigger, or view |
| name | Name of the database object |
| tbl_name | The table name that the database object is associated with |
| rootpage | The root page |
| sql | SQL used to create the database object |
SELECT name FROM sqlite_master
WHERE type='table'
ORDER BY name;
To get a complete list of all tables in a database powered by SQLite:
select table_name
from information_schema.tables
where table_type = 'BASE TABLE' and table_schema = database();
To get a complete list of all tables in a database powered by MySQL:
SELECT * FROM information_schema.tables;
To get a complete list of all tables in a database powered by PostgreSQL:
SELECT table_name FROM dba_tables;
To get a complete list of all tables in a database powered by Oracle:
SQL explained
By Christophe Limpalair
