SQL SELECT MIN

SQL SELECT MIN

MIN是SQL中的一个聚合函数,它从表中某一列的多个值中返回最小值。

SQL Min()函数的语法

SELECT MIN(Column_Name) FROM Table_Name WHERE [Condition];

在这个语法中,我们还可以在使用WHERE子句时使用MIN函数来选择过滤记录中的最小值。

两个SQL Min函数的示例

示例1:此示例描述了如何在SQL中使用MIN函数。

让我们创建一个简单的表,然后在该表上运行MIN函数。

以下CREATE TABLE语句创建了一个名为Bikes_Details的表,包含五个字段:

CREATE TABLE Bikes_Details
(
Bike_Number INT PRIMARY KEY,
Bike_Model INT,
Bike_Name VARCHAR (50),
Number_of_Bikes INT NOT NULL
Bike_Price INT NOT NULL
) ;

以下INSERT查询将汽车记录插入Bikes_Details表中:

INSERT INTO Bikes_Details (Bike_Number, Bike_Model, Bike_Name, Number_of_Bikes, Bike_Price) 
VALUES (2578, 2018, KTM, 3, 1500000),
(9258, 2019, Apache, 2, 3000000), 
(8233, 2018, Pulsar, 6, 900000),
(8990, 2018, RX100, 7, 700000),
(9578, 2020, Splender+, 6, 8000000),
(1258, 2021, Bullet, 2, 1500000),
(2564, 2019, Passion, 4, 6000000),
(2155, 2020, Livo, 8, 1800000);

下面的SELECT查询显示了 Bikes_Details 表的数据:

SELECT * FROM Bikes_Details;
Bike_Number Bike_Model Bike_Name Number_of_Bikes Bike_Price
2578 2018 KTM 3 900000
9258 2019 Apache 2 1100000
8233 2018 Pulsar 6 900000
8990 2018 RX100 7 700000
9578 2020 Splender+ 6 8000000
1258 2021 Buller 2 1500000
2564 2019 Passion 4 6000000
2155 2020 Livo 8 1800000

以下查询显示了上述Bikes_Details表中Bike_Number列的最小值:

SELECT MIN(Bike_Number) As "Smallest Bike Number " FROM Bikes_Details;

输出:

SQL SELECT MIN

示例2:这个例子向你展示如何在WHERE子句中使用MIN函数。

以下查询使用CREATE TABLE语句创建了 College_Student_Details 表:

CREATE TABLE College_Student_Details
(
Student_ID INT NOT NULL, 
Student_Name varchar(100),
Student_Course varchar(50),
Student_Age INT, 
Student_Marks INT
); 

以下SQL查询使用INSERT INTO语句将学生记录插入上述表中:

INSERT INTO College_Student_Details VALUES (101, Anuj, B.tech, 20, 88);
INSERT INTO College_Student_Details VALUES (102, Raman, MCA, 24, 98);
INSERT INTO College_Student_Details VALUES (104, Shyam, BBA, 19, 92);
INSERT INTO College_Student_Details VALUES (107, Vikash, B.tech, 20, 78);
INSERT INTO College_Student_Details VALUES (111, Monu, MBA, 21, 65);
INSERT INTO College_Student_Details VALUES (114, Jones, B.tech, 18, 93);
INSERT INTO College_Student_Details VALUES (121, Parul, BCA, 20, 97);
INSERT INTO College_Student_Details VALUES (123, Divya, B.tech, 21, 89);
INSERT INTO College_Student_Details VALUES (128, Hemant, MBA, 23, 90);
INSERT INTO College_Student_Details VALUES (130, Nidhi, BBA, 20, 88);
INSERT INTO College_Student_Details VALUES (132, Priya, MBA, 22, 99);
INSERT INTO College_Student_Details VALUES (138, Mohit, MCA, 21, 92);

让我们使用以下SELECT语句来查看上表的记录:

SELECT * FROM College_Student_Details;
Student_ID Student_Name Student_Course Student_Age Student_Marks
101 Anuj B.tech 20 88
102 Raman MCA 24 98
104 Shyam BBA 19 92
107 Vikash B.tech 20 78
111 Monu MBA 21 65
114 Jones B.tech 18 93
121 Parul BCA 20 97
123 Divya B.tech 21 89
128 Hemant MBA 23 90
130 Nidhi BBA 20 88
132 Priya MBA 22 99
138 Mohit MCA 21 92

以下MIN查询显示了College_Student_Details表中Student_Marks列中大于70的最低分数:

SELECT MIN(Student_Marks) As "Lowest Marks Above 70" FROM College_Student_Details WHERE Student_Marks > 70;

输出:

SQL SELECT MIN

MIN 函数与 SQL GROUP BY 子句

使用 GROUP BY 子句的 MIN 函数显示表中每个组中的最小值。

使用 MIN 函数和 GROUP BY 子句的语法如下所示:

SELECT Column_Name_1, MIN(Column_Name) FROM Table_Name GROUP BY Column_Name_1;

MIN函数与GROUP BY子句的示例

让我们使用上述College_Student_Details表来理解MIN函数与GROUP BY子句的概念。

以下查询显示了上述College_Student_Details表中每门课程中学生的最低分数:

SELECT Student_Course, MIN (Student_Marks) FROM College_Student_Details GROUP BY Student_Course;

输出:

Student_Course MIN (Student_Marks)
B.tech 78
MCA 92
BBA 88
MBA 65
BCA 97

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