按照学生平均成绩(avg_grade) 将students表中的数据检索出来,下面SQL语句正确的是? ( )A. SELECT * FROM students ORDER BY avg_grade B. SELECT * FROM students GROUP BY avg_grade ASC C. SELECT * FROM students ORDER BY avg_grade DESC D. SELECT * FROM students ORDER by avg_grade asc ...
下面选项中,能够按照grade由高到低显示student表中记录的SQL语句是A、SELECT * FROM student ORDER BY grade;B、SELECT * FROM student ORDER BY grade ASC;C、SELECT * FROM student ORDER BY grade DESC;D、SELECT * FROM student GROUP BY grade DESC;...
from tb_order_overall),event_time) between 0 and 89 and status = 1 group by uid,product_id)a group by product_id order by repurchase_rate desc,product_id asc limit 3 再补充个二刷时候的新思路,用窗口函数,一次group by出结果,不需要建立临时表 select distinct a.product_id, round(avg(count...
由于使用了GROUP BY子句,因此针对每个销售订单只返回一行销售总额。 G. 对多个组使用 GROUP BY 以下示例查找按产品 ID 和特价产品 ID 分组的平均价格和迄今为止的年销售总额。 SQL USEAdventureWorks2022; GOSELECTProductID, SpecialOfferID,AVG(UnitPrice)AS[Average Price],SUM(LineTotal)ASSubTotalFROMSales.Sales...
数据库中有students表,字段如下:sno(学号-主键),sname(学生姓名-非空),xb(性别-非空),zhy(专业-非空),in_year(入学年份),dept(所在系部)。teachers表,字段如下:tno(教师号-主键),tname(教师姓名-非空),txb(教师性别-非空),zc(职称),age(年龄)。下面的查询结果是以上两个表的笛卡尔乘积的是:() A....
J. 使用 GROUP BY 與 ORDER BY 下列範例會尋找各項產品類型的平均價格,且會依照平均價格來排序結果。 SQL複製 USEAdventureWorks2022; GOSELECTProductID,AVG(UnitPrice)AS[Average Price]FROMSales.SalesOrderDetailWHEREOrderQty >10GROUPBYProductIDORDERBYAVG(UnitPrice); GO ...
SELECTOrderDateKey, PromotionKey,AVG(SalesAmount)ASAvgSales,SUM(SalesAmount)ASTotalSalesFROMFactInternetSalesGROUPBYOrderDateKey, PromotionKeyORDERBYOrderDateKey; F. Use GROUP BY and WHERE The following example puts the results into groups after retrieving only the rows with order dates later than ...
FROM 數據表中的欄位,也是主要 SELECT 子句中的選取專案, (不在子查詢) 。 數值表達式,表示結果表中數據行的位置。 (最左邊的數據行是數位 1.) ASC 會根據訂單專案或專案指定查詢結果的遞增順序,而且是 ORDER BY 的預設值。DESC 會指定查詢結果的遞減順序。
GROUP BY: 对结果进行分组,通常与聚合函数(SUM, AVG, COUNT)一起使用。 HAVING条件: 对GROUP BY的结果进行条件过滤,类似于WHERE但用于分组后的数据。 ORDER BY: 对结果进行排序,可指定一个或多个列,以及升序(ASC)或降序(DESC)。 示例: -- 基本查询 SELECT first_name, last_name FROM employees; -- 查询...
FROM table_source [ WHERE search_condition ] [ GROUP BY group_by_expression ] [ HAVING search_condition ] [ ORDER BY order_expression [ASC| DESC ]] 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 参数: select_list:指定由查询返回的列。它是一个逗号分隔的表达式列表。每个表达式同...