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题解 | #商品交易(网易校招笔试真题)#

```SELECT style_id, COUNT( style_id ) AS SPU_num FROM product_tb GROUP BY style_id ORDER BY SPU_num DESC;

Mysql

2022-02-19

0 296

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT *, DATE_FORMAT( event_time, "%Y-%m" ) AS year_mont FROM tb_order_overall ) SELECT t.year_mont AS MONTH, ROUND( sum( t.total_amou...

Mysql

2022-02-19

0 286

题解 | #商品交易(网易校招笔试真题)#

```WITH t AS ( SELECT *, TIMESTAMPDIFF( SECOND, in_time, out_time ) AS subtime, date( in_time ) days FROM tb_user_log WHERE YEAR ( in_t...

Mysql

2022-02-18

0 357

题解 | #商品交易(网易校招笔试真题)#

WITH t AS ( SELECT CASE WHEN TIMESTAMPDIFF( SECOND, t1.start_time, t1.end_time ) >= t2.duration THEN 100 ELSE TIMESTAMPDIFF( SECOND, t1.start...

Mysql

2022-02-18

0 264

题解 | #商品交易(网易校招笔试真题)#

SELECT g.*, t1.total total FROM goods g INNER JOIN ( SELECT t.goods_id, SUM( t.count ) total FROM goods g LEFT JOIN trans t ON g.id = t.goods_id GROUP...

Mysql

2022-02-14

0 249

题解 | #查找薪水记录超过15次的员工号emp_no以及其对应的记录次数t#

```SELECT o.id id, o.is_group_buy is_group_buy, IFNULL(NULL,c.`name`) NAME FROM order_info o LEFT JOIN client c ON o.client_id = c.id WHERE use...

Mysql

2022-02-14

0 281

题解 | #查找薪水记录超过15次的员工号emp_no以及其对应的记录次数t#

SELECT * FROM employees WHERE emp_no % 2 != 0 AND last_name != 'Mary' ORDER BY hire_date DESC; 针对单表的查询排序问题，根据emp_no找到编号为奇数的记录，再根据last_name筛选掉姓名是Mary的记...

Sqlite

2022-02-13

0 261

题解 | #查找薪水记录超过15次的员工号emp_no以及其对应的记录次数t#

SELECT * FROM ( SELECT emp_no, COUNT( emp_no ) AS t FROM salaries GROUP BY emp_no ) AS sal WHERE sal.t > 15; 根据emp_no分组形成emp_no和统计次数t的临时表，从临时表中查询出t...

Sqlite

2022-02-13

1 189

题解 | #替换空格#

替换不可变字符串空格：借助一个可变字符串，遍历原字符串如若是原字符进行追加，空格则替换为%20再追加。 public String replaceSpace(String s) { // write code here int length = s.leng...

Java 字符串

2021-12-24

0 350

题解 | #数组中出现次数超过一半的数字#

取数组长度超过一半的数字，即取中间位置的数字。排序数组，返回中间位数字。另外需排除数组长度为1的情况。 public int MoreThanHalfNum_Solution(int [] array) { // 排序数组 // Arrays.sort(array); if (array.lengt...

Java 数组

2021-12-24

0 240