# SQL LCASE() 函数

## LCASE() 函数

LCASE() 函数把字段的值转换为小写。

### SQL LCASE() 语法

     SELECT LCASE(column_name) FROM table_name;

### 用于 SQL Server 的语法

     SELECT LOWER(column_name) FROM table_name;

## 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 snabbköp | Christina Berglund | Berguvsvägen 8 | Luleå | S-958 22 | Sweden

## SQL LCASE() 实例

下面的 SQL 语句从 "Customers" 表中选取 "CustomerName" 和 "City" 列，并把 "CustomerName" 列的值转换为小写：

## 实例

     SELECT LCASE(CustomerName) AS Customer, City
    FROM Customers;