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PostgreSQL 选择数据


选择数据

要从数据库中检索数据,我们使用 SELECT 语句。


指定列

通过指定列名,我们可以选择要选择的列

示例

SELECT customer_name, country FROM customers;
运行示例 »

返回所有列

指定 * 而不是列名以选择所有

示例

SELECT * FROM customers;
运行示例 »

PostgreSQL 练习

通过练习测试自己

练习

编写正确的 SQL 语句以从 customers 表中选择 citycountry 列。

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开始练习


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