学校教材发放管理系统中的免费策略实现

CREATE TABLE Students (

student_id INT PRIMARY KEY,

name VARCHAR(50),

class VARCHAR(50)

);

CREATE TABLE Textbooks (

textbook_id INT PRIMARY KEY,

title VARCHAR(100),

author VARCHAR(100)

);

研究生管理信息系统

CREATE TABLE FreeTextbooks (

student_id INT,

textbook_id INT,

FOREIGN KEY (student_id) REFERENCES Students(student_id),

FOREIGN KEY (textbook_id) REFERENCES Textbooks(textbook_id)

);

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function distributeFreeTextbooks($student_id, $textbook_id) {

// 检查学生是否已经领取了该教材

if (!checkIfStudentHasTextbook($student_id, $textbook_id)) {

// 插入到FreeTextbooks表中

insertIntoFreeTextbooks($student_id, $textbook_id);

return true;

}

return false;

}

function checkIfStudentHasTextbook($student_id, $textbook_id) {

// 查询数据库

$query = "SELECT * FROM FreeTextbooks WHERE student_id = $student_id AND textbook_id = $textbook_id";

// 执行查询并返回结果

return executeQuery($query);

}

function insertIntoFreeTextbooks($student_id, $textbook_id) {

$query = "INSERT INTO FreeTextbooks (student_id, textbook_id) VALUES ($student_id, $textbook_id)";

executeQuery($query);

}

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