The conflict occurred in database " - mysql

Question

I have the code here, but it was written by my teachers
create database abc_quanlybanhang111111;
use abc_quanlybanhang111111;
create table abc_nhacc
(
MaCC1 varchar(10) primary key,
TenNhaCC varchar(50) not null,
DiaChiCC varchar(50),
PhoneCC varchar(11),
);
create table abc_mamh
(
MaMH1 varchar(50) primary key,
TenMH varchar(100),
DonGia int,
SoLuong int,
MaCC1 varchar(10) foreign key references abc_nhacc(MaCC1)
);
create table abc_khachhang
(
MaMh1 VARCHAR(10) PRIMARY KEY,
TenKh varchar(50),
DiaChi varchar(50),
SĐT int,
);
CREATE TABLE abc_donhang
(
MaDH1 varchar(10) primary key,
NgayDH DATE default GetDate(),
MaKH1 varchar(10) foreign key references abc_khachhang(MaMH1)
);
create table abc_chitietdonhang
(
MaDH1 varchar(10) foreign key references abc_donhang(MaDH1) ,
MaMH1 varchar(50) foreign key references abc_mamh(MaMH1),
SoLuong int check (soluong>0)
constraint pk_dmhh primary key ( MaDH1, MaMH1)
);
insert into abc_nhacc
values
('K001', 'THE GIOI DI DONG', '121 TRAN QUANG KHAI', '0164789720'),
('K002', 'NGUYEN KIM', '12 TRAN PHU', '0161792793'),
('K003', 'THIEN HOA', '2 BA HUYEN THANH QUAN', '094850873'),
('K004', 'PHONG VU', '32 LE VAN VIET QUAN 9', '85839201'),
('K005', 'TAN BINH', '14 NGUYEN THI DINH', '0912012901')
SELECT *
FROM abc_nhacc;
insert into abc_mamh
values
('S001', 'MSI ACER GAMING', 2000000, 1, 'K001');
insert into abc_mamh
values
('S002', 'MSI ASUS GAMING', 1000000, 10, 'K002'),
('S003', 'MSI GAMING', 1100000, 1, 'K003'),
('S004', 'LENOVO GAMING', 2000, 111, 'K004'),
('S005', 'IPHONE', 120000, 1, 'K005')
SELECT *
FROM abc_mamh;
insert into abc_khachhang
values
('KH1', 'LONG NGUYEN', '12 TRAN QUANG DIEU QUAN 1', '0938078972');
insert into abc_khachhang
values
('KH2', 'THONG NGUYEN', '1 TRAN DIEU QUAN 2', '0968071972'),
('KH3', 'THANH NGUYEN', '23 NGUYEN THI DINH QUAN 8', '0138073972'),
('KH4', 'THINH NGUYEN', '1 TRUONG DINH QUAN 1', '016479828'),
('KH5', 'LINH TRAN', '2 TRAN QUANG KHAI QUAN 1', '0938078122')
SELECT *
FROM abc_mamh;
insert into abc_chitietdonhang
values('DH001', 'MH001', 2),
('DH002', 'MH002', 3),
('DH003', 'MH003', 1),
('DH004', 'MH004', 9),
('DH004', 'MH005', 4),
('DH003', 'MH006', 11),
('DH001', 'MH007', 12);
I have try to fix the code with the step delete the foreign key but it always show errors after I delete it :
Msg 547, Level 16, State 0, Line 72
The INSERT statement conflicted with the FOREIGN KEY constraint "FK__abc_chiti__MaDH1__4222D4EF". The conflict occurred in database "abc_quanlybanhang1111111", table "dbo.abc_donhang", column 'MaDH1'
Please help me learn how to can fix this errors. Thank.

Answer 1

You have to add the rows in abc_donhang which you are trying to reference in your insert into abc_chitietdonhang ... query. You try to reference the row with the Id DH001, but it doesn't exists (yet). Same goes for the Id MH001, it doesn't exists in the abc_mamh table either.