https://leetcode.cn/studyplan/sql-free-50/ 查询 查询的结构 #方式1: SELECT ...,...,... FROM ...,...,... WHERE 多表的连接条件 AND 不包含组函数的过滤条件 GROUP BY ...,... HAVING
number-of-students-doing-homework-at-a-given-time number-of-students-unable-to-eat-lunch number-of-subarrays-with-bounded-maximum number-of-subarrays-with-gcd-equal-to-k number-of-subarrays-with-lcm-equal-to-k number-of-unequal-triplets-in-array number-of-valid-clock-times number...
And we defined a friend circle is a group of students who are direct or indirect friends. Given a N*N matrix M representing the friend relationship between students in the class. If M[i][j] = 1, then the ith and jth students are direct friends with each other, otherwise not. And yo...
/ 示例 1: 输入:students = [1,1,0,0], sandwiches = [0,1,0,1] 输出:0 解释: 最前面的学生放弃最顶上的三明治,并回到队列的末尾,学生队列变为 students = [1,0,0,1]。 最前面的学生放弃最顶上的三明治,并回到队列的末尾,学生队列变为 students = [0,0,1,1]。 最前面的学生拿走最顶上的三...
1349.Maximum-Students-Taking-Exam (H) 1411.Number-of-Ways-to-Paint-N×3-Grid (M) 1434.Number-of-Ways-to-Wear-Different-Hats-to-Each-Other (H-) 1659.Maximize-Grid-Happiness (H) 1681.Minimum-Incompatibility (H) 1723.Find-Minimum-Time-to-Finish-All-Jobs (H-) 1799.Maximize-Score-After...
1700 Number of Students Unable to Eat Lunch Go 67.7% Easy 1701 Average Waiting Time 62.3% Medium 1702 Maximum Binary String After Change 46.1% Medium 1703 Minimum Adjacent Swaps for K Consecutive Ones 41.3% Hard 1704 Determine if String Halves Are Alike Go 77.4% Easy 1705 Maximum Numbe...
596. Classes More Than 5 Students Poblem: Please list out all classes which have more than or equal to 5 students. GROUP BY + Subquery 建表语句: create table 表名( //表名一般以 t_ 或 tbl_ 开始,且不能以数字开头 字段名1 数据类型, 字段名2 数据类型, … ); 可能存在重复记......
LeetCode 197. Rising Temperature LeetCode 181. Employees Earning More Than Their Managers LeetCode 627. Swap Salary LeetCode 620. Not Boring Movies LeetCode 596. Classes More Than 5 Students LeetCode196. Delete Duplicate Emails LeetCode176. Second Highest Salary ...
# 首先是要用cross join笛卡尔积将students表和subjects表合成一个12行的表,接着和Examinations表左连接,求attended_exams时记得用e.subject_name而不是b.subject_name,因为用count函数可以把那些null视为0,即没有上课的人会视为0。 SELECT s.student_id, s.student_name, b.subject_name, COUNT(e.subject_nam...
+---+---+ | Column Name | Type | +---+---+ | box_id | int | | chest_id | int | | apple_count | int | | orange_count | int | +---+---+ box_id is the primary key for this table. chest_id is a foreign key of the chests table. This table contains information ...