sql存储过程，根据校区算出>=60岁、>=50岁、>=40岁、>=30岁和30岁以下的人数，然后相加总人数

好的，这是一个比较典型的统计存储过程，可以按照以下步骤实现：

1. 创建存储过程并输入参数

CREATE PROCEDURE count_age_by_campus
    @campus varchar(50)
AS

2. 声明变量并初始化

DECLARE @age60 INT, @age50 INT, @age40 INT, @age30 INT, @age_under30 INT, @total INT
SET @age60 = 0
SET @age50 = 0
SET @age40 = 0
SET @age30 = 0
SET @age_under30 = 0
SET @total = 0

3. 查询并统计各年龄段人数

SELECT 
    @age60 = COUNT(*) 
FROM 
    student 
WHERE 
    campus = @campus AND 
    DATEDIFF(yy, birthdate, GETDATE()) >= 60

SELECT 
    @age50 = COUNT(*) 
FROM 
    student 
WHERE 
    campus = @campus AND 
    DATEDIFF(yy, birthdate, GETDATE()) >= 50 AND 
    DATEDIFF(yy, birthdate, GETDATE()) < 60

SELECT 
    @age40 = COUNT(*) 
FROM 
    student 
WHERE 
    campus = @campus AND 
    DATEDIFF(yy, birthdate, GETDATE()) >= 40 AND 
    DATEDIFF(yy, birthdate, GETDATE()) < 50

SELECT 
    @age30 = COUNT(*) 
FROM 
    student 
WHERE 
    campus = @campus AND 
    DATEDIFF(yy, birthdate, GETDATE()) >= 30 AND 
    DATEDIFF(yy, birthdate, GETDATE()) < 40

SELECT 
    @age_under30 = COUNT(*) 
FROM 
    student 
WHERE 
    campus = @campus AND 
    DATEDIFF(yy, birthdate, GETDATE()) < 30

4. 计算总人数

SET @total = @age60 + @age50 + @age40 + @age30 + @age_under30

5. 返回结果

SELECT 
    @age60 AS age60, 
    @age50 AS age50, 
    @age40 AS age40, 
    @age30 AS age30, 
    @age_under30 AS age_under30, 
    @total AS total

完整的存储过程如下：

CREATE PROCEDURE count_age_by_campus
    @campus varchar(50)
AS
BEGIN
    DECLARE @age60 INT, @age50 INT, @age40 INT, @age30 INT, @age_under30 INT, @total INT
    SET @age60 = 0
    SET @age50 = 0
    SET @age40 = 0
    SET @age30 = 0
    SET @age_under30 = 0
    SET @total = 0

    SELECT 
        @age60 = COUNT(*) 
    FROM 
        student 
    WHERE 
        campus = @campus AND 
        DATEDIFF(yy, birthdate, GETDATE()) >= 60

    SELECT 
        @age50 = COUNT(*) 
    FROM 
        student 
    WHERE 
        campus = @campus AND 
        DATEDIFF(yy, birthdate, GETDATE()) >= 50 AND 
        DATEDIFF(yy, birthdate, GETDATE()) < 60

    SELECT 
        @age40 = COUNT(*) 
    FROM 
        student 
    WHERE 
        campus = @campus AND 
        DATEDIFF(yy, birthdate, GETDATE()) >= 40 AND 
        DATEDIFF(yy, birthdate, GETDATE()) < 50

    SELECT 
        @age30 = COUNT(*) 
    FROM 
        student 
    WHERE 
        campus = @campus AND 
        DATEDIFF(yy, birthdate, GETDATE()) >= 30 AND 
        DATEDIFF(yy, birthdate, GETDATE()) < 40

    SELECT 
        @age_under30 = COUNT(*) 
    FROM 
        student 
    WHERE 
        campus = @campus AND 
        DATEDIFF(yy, birthdate, GETDATE()) < 30

    SET @total = @age60 + @age50 + @age40 + @age30 + @age_under30

    SELECT 
        @age60 AS age60, 
        @age50 AS age50, 
        @age40 AS age40, 
        @age30 AS age30, 
        @age_under30 AS age_under30, 
        @total AS total
END

使用方法：

EXEC count_age_by_campus 'A校区'

其中，'A校区'为参数，可以根据实际情况进行修改。