SQL SELECT

Internal

• SQL
• SQL WHERE

Overview

A query consists in at least one (SELECT) and at most six categories of clauses:

SELECT [...] FROM [...] WHERE [...] GROUP BY [...] HAVING [...] ORDER BY [...]

The following query:

SELECT;

is valid, it returns one empty row.

Upon execution, an SQL query returns a result set.

Select all (possibly across multiple tables) then filter and discard with where.

Example

SELECT id, name FROM person WHERE id = 1;

Clauses

FROM

FROM permanent|derived|temporary|virtual(view)

Table alias.

Querying Multiple Tables

Querying Multiple Tables

WHERE

The WHERE Clause

GROUP BY ... HAVING

GROUP BY ... HAVING