c# - 如何在不同的表中写入我的 FK 值？ C# | SQLite

Question

我正在开展一个学校项目，其中我正在创建一个客户管理系统。由于一项要求，我需要将数据库模式从使用 1 个表更改为使用 2 个表。目前，我可以写入数据库中的两个表，但是，我在获取外键的概念时遇到了困难。我的 SQL 经验非常有限。我当前的执行语句正在写入除 MedicalInformation 表中的客户端 ID 列之外的两个表。它显示为空，我不确定应该如何从这里继续。

cnn.Execute("INSERT INTO ClientInformation (FirstName, MiddleInitial, LastName, Phone, Email, Address, City, State, Zip, DateOfBirth, Occupation, Employer, EmergencyContact, EmergencyContactRelationship, EmergencyContactPhone) " +
            "VALUES (@FirstName, @MiddleInitial, @LastName, @Phone, @Email, @Address, @City, @State, @Zip, @DateOfBirth, @Occupation, @Employer, @EmergencyContact, @EmergencyContactRelationShip, @EmergencyContactPhone)", client);


cnn.Execute("INSERT INTO MedicalInformation (CurrentMedications, ChronicPain, ChronicPainWhere, OrthopedicPain, OrthopedicPainWhere, Pregnant, PreferedPressureLight, PreferedPressureMedium, PreferedPressureDeep, Allergies, AllergiesWhat, Cancer, HeadacheMigraine, Arthritis, Diabetes, JointReplacement, HighLowBloodPressure, Neuropathy, Fibromyalgia, Stroke, HeartAttack, KidneyDysfunction, BloodClots, Numbness, SprainsStrains, AreasOfDiscomfort) " +
            "VALUES (@CurrentMedication, @ChronicPain, @ChronicPainWhere, @OrthopedicPain, @OrthopedicPainWhere, @Pregnant, @PeferredPressureLight, @PeferredPressureMedium, @PeferredPressureDeep, @Allergies, @AllergiesWhat, @Cancer, @HeadacheMigraine, @Arthritis, @Diabetes, @JointReplacement, @HighLowBloodPressure, @Neuropathy, @Fibromyalgia, @Stroke, @HeartAttack, @KidneyDysfunction, @BloodClots, @Numbness, @SprainsStrains, @AreasOfDiscomfort) ", client.MedicalInfo);

这是表格的一部分

CREATE TABLE "MedicalInformation" (
    "_ID"   INTEGER NOT NULL UNIQUE,
    "Client_ID" INTEGER,
    
    PRIMARY KEY("_ID" AUTOINCREMENT),
    FOREIGN KEY("Client_ID") REFERENCES "ClientInformation"("Client_Id")
);

CREATE TABLE "ClientInformation" (
    "Client_Id" INTEGER NOT NULL UNIQUE,
   
    PRIMARY KEY("Client_Id" AUTOINCREMENT)
);

我的 clientinfo 类

public class ClientInformation
    {
        //Client Information
        public int Client_ID { get; set; }
        public string FirstName { get; set; }
        public string MiddleInitial { get; set; }
        public string LastName { get; set; }
        public string Phone { get; set; }
        public string Email { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string State { get; set; }
        public string Zip { get; set; }
        public string DateOfBirth { get; set; }
        public string Occupation { get; set; }
        public string Employer { get; set; }
        public string EmergencyContact { get; set; }
        public string EmergencyContactRelationship { get; set; }
        public string EmergencyContactPhone { get; set; }
        public MedicalInformation MedicalInfo { get; set; }
        public ClientInformation(string firstname, string middleinitial, string lastname, string phone, string email, string address, string city, string state, string zip, string dateofbirth, string occupation, string employer,
        string emergencycontact, string emergencycontactrelationship, string emergencycontactphone, MedicalInformation clientMedicainfo)
        {
            this.FirstName = firstname;
            this.MiddleInitial = middleinitial;
            this.LastName = lastname;
            this.Phone = phone;
            this.Email = email;
            this.Address = address;
            this.City = city;
            this.State = state;
            this.Zip = zip;
            this.DateOfBirth = dateofbirth;
            this.Occupation = occupation;
            this.Employer = employer;
            this.EmergencyContact = emergencycontact;
            this.EmergencyContactRelationship = emergencycontactrelationship;
            this.EmergencyContactPhone = emergencycontactphone;
            this.MedicalInfo = clientMedicainfo;
        }

    }

Answer 1

由于您的 ClientInformation.Client_Id key 是由 SQLite 自动生成的，因此您需要在插入 MedicalInformation 表之前以某种方式检索它。

我对 SQLite 没有经验，但快速浏览了一下 SQLite documentation ，我发现您可以使用 last_insert_rowid() 函数来检索最后一行插入的 ID。

您将需要在 client.MedicalInfo 对象中使用此 Client_ID 值以便稍后处理，因此我认为可以执行以下操作:

client.MedicalInfo.Client_ID = cnn.ExecuteScalar<int>("INSERT INTO ClientInformation (FirstName, MiddleInitial, LastName, Phone, Email, Address, City, State, Zip, DateOfBirth, Occupation, Employer, EmergencyContact, EmergencyContactRelationship, EmergencyContactPhone) " +
            "VALUES (@FirstName, @MiddleInitial, @LastName, @Phone, @Email, @Address, @City, @State, @Zip, @DateOfBirth, @Occupation, @Employer, @EmergencyContact, @EmergencyContactRelationShip, @EmergencyContactPhone);" +
            "SELECT last_insert_rowid();", client);

cnn.Execute("INSERT INTO MedicalInformation (Client_ID, CurrentMedications, ChronicPain, ChronicPainWhere, OrthopedicPain, OrthopedicPainWhere, Pregnant, PreferedPressureLight, PreferedPressureMedium, PreferedPressureDeep, Allergies, AllergiesWhat, Cancer, HeadacheMigraine, Arthritis, Diabetes, JointReplacement, HighLowBloodPressure, Neuropathy, Fibromyalgia, Stroke, HeartAttack, KidneyDysfunction, BloodClots, Numbness, SprainsStrains, AreasOfDiscomfort) " +
            "VALUES (@Client_ID, @CurrentMedication, @ChronicPain, @ChronicPainWhere, @OrthopedicPain, @OrthopedicPainWhere, @Pregnant, @PeferredPressureLight, @PeferredPressureMedium, @PeferredPressureDeep, @Allergies, @AllergiesWhat, @Cancer, @HeadacheMigraine, @Arthritis, @Diabetes, @JointReplacement, @HighLowBloodPressure, @Neuropathy, @Fibromyalgia, @Stroke, @HeartAttack, @KidneyDysfunction, @BloodClots, @Numbness, @SprainsStrains, @AreasOfDiscomfort); ", client.MedicalInfo);

只需确保 DTO 类中存在 client.MedicalInfo.Client_ID 属性即可。