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PostgreSQL SUM 函数


SUM

The SUM() 函数返回数值列的总和。

以下 SQL 语句查找 order_details 表中 quantity 字段的总和

示例

返回已订购商品的总数量

SELECT SUM(quantity)
FROM order_details;
运行示例 »

注意: NULL 值将被忽略。


PostgreSQL 练习

通过练习测试自己

练习

使用正确的函数返回 products 表中 price 字段所有值的总和。

SELECT 
FROM products;
        

开始练习


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