SQL FIRST() Function

A FIRST() Function

A FIRST() função retorna o primeiro valor da coluna selecionada.

SELECT FIRST(column_name) FROM table_name;

Note: A FIRST() função só é suportada no MS Access.

SELECT TOP 1 column_name FROM table_name
ORDER BY column_name ASC;

SELECT TOP 1 CustomerName FROM Customers
ORDER BY CustomerID ASC;

SELECT column_name FROM table_name
ORDER BY column_name ASC
LIMIT 1;

SELECT CustomerName FROM Customers
ORDER BY CustomerID ASC
LIMIT 1;

SELECT column_name FROM table_name
WHERE ROWNUM <=1
ORDER BY column_name ASC;

SELECT CustomerName FROM Customers
WHERE ROWNUM <=1
ORDER BY CustomerID ASC;

Neste tutorial, vamos utilizar a base de dados conhecida exemplo Adamastor.

Abaixo está uma seleção do "Customers" da tabela:

CustomerID	CustomerName	ContactName	Address	City	PostalCode	Country
1	Alfreds Futterkiste	Maria Anders	Obere Str. 57	Berlin	12209	Germany
2	Ana Trujillo Emparedados y helados	Ana Trujillo	Avda. de la Constitucion 2222	Mexico D.F.	05021	Mexico
3	Antonio Moreno Taqueria	Antonio Moreno	Mataderos 2312	Mexico D.F.	05023	Mexico
4	Around the Horn	Thomas Hardy	120 Hanover Sq.	London	WA1 1DP	UK
5	Berglunds snabbkop	Christina Berglund	Berguvsvagen 8	Lulea	S-958 22	Sweden

A seguinte instrução SQL seleciona o primeiro valor do "CustomerName" coluna do "Customers" da tabela:

SELECT FIRST(CustomerName) AS FirstCustomer FROM Customers;