SQLFIRST() 函数
FIRST() 函数
FIRST() 函数返回指定的列中第一个记录的值。
SQL FIRST() 语法
SELECT FIRST(column_name) FROM table_name;
注释：只有 MS Access 支持 FIRST() 函数。
SQL Server、MySQL 和 Oracle 中的 SQL FIRST() 工作区
SQL Server 语法
SELECT TOP 1 column_name FROM table_name
ORDER BY column_name ASC;
实例
SELECT TOP 1 CustomerName FROM Customers
ORDER BY CustomerID ASC;
MySQL 语法
SELECT column_name FROM table_name
ORDER BY column_name ASC
LIMIT 1;
实例
SELECT CustomerName FROM Customers
ORDER BY CustomerID ASC
LIMIT 1;
Oracle 语法
SELECT column_name FROM table_name
ORDER BY column_name ASC
WHERE ROWNUM <=1;
实例
SELECT CustomerName FROM Customers
ORDER BY CustomerID ASC
WHERE
ROWNUM <=1;
演示数据库
在本教程中，我们将使用众所周知的 Northwind 样本数据库。
下面是选自 "Customers" 表的数据：
|
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 Constitución 2222
|
México D.F.
|
05021
|
Mexico
|
|
3
|
Antonio Moreno Taquería
|
Antonio Moreno
|
Mataderos 2312
|
México D.F.
|
05023
|
Mexico
|
4
|
Around the Horn
|
Thomas Hardy
|
120 Hanover Sq.
|
London
|
WA1 1DP
|
UK
|
|
5
|
Berglunds snabbk?p
|
Christina Berglund
|
Berguvsv?gen 8
|
Lule?
|
S-958 22
|
Sweden
|
SQL FIRST() 实例
下面的 SQL 语句选取 "Customers" 表的 "CustomerName" 列中第一个记录的值：
实例
SELECT FIRST(CustomerName) AS FirstCustomer FROM Customers;
