Foreign key references invalid column error in MS SQL - sql

Question

This is all in MS SQL.
I've seen this issue pop up a lot, and I searched around but I still can't figure out my issue. I'm getting the error telling me my foreign key references in invalid column in an uncreated table. However, I created the table as it shows up on my database table list, so it shows it is created.
I tried to move that said table above the table that references it, yet I'm still receiving the error. Would anyone know how to fix this?
My code:
CREATE SCHEMA usr_in;
go
CREATE TABLE gender_interst (
id int IDENTITY (1,1),
gend_id int
CONSTRAINT gender_interstpk PRIMARY KEY (id)
)
CREATE TABLE gender (
id int IDENTITY (1,1),
gend VARCHAR (20)
CONSTRAINT genderpk PRIMARY KEY (id)
);
SELECT * FROM gender_interst LEFT JOIN gender on gender_interst.id = gender.id;
SELECT * from gender_interst;
CREATE TABLE user_info (
id int PRIMARY KEY IDENTITY (1,1),
usr_name VARCHAR (30) NOT NULL,
f_name VARCHAR (30) NOT NULL,
l_name VARCHAR (30),
b_day DATE,
email VARCHAR (120) NOT NULL,
genderpkid VARCHAR (10) NOT NULL,
CONSTRAINT gender_fk FOREIGN KEY (genderpkid) REFERENCES gender (genderpk),
);
INSERT
INTO user_info
( usr_name, f_name, l_name, b_day, genderpkid, email)
VALUES
('JMAN', 'JOHN', 'DOE', '1990-01-01','M','EX#EMAIL'),
('JAM','JANE', 'DOE', '1995-05-02','F','EX#EMAIL'),
('NMAN','NICK', 'WEBB', '1999-06-22','M','EX#EMAIL'),
('LOBA','LOLA', 'LILLY', '1994-01-08','F','EX#EMAIL'),
('NOTSPMAN','PETER', 'PARKER','1985-11-25','M','EX#EMAIL');
SELECT * FROM user_info;

Answer 1

Your foreign key needs to reference the name of a table column (which is either id or gend) and not the name of the primary key (genderpk).
Therefore the foreign key script (CONSTRAINT gender_fk FOREIGN KEY (genderpkid) REFERENCES gender (genderpk)) should look something like CONSTRAINT gender_fk FOREIGN KEY (genderpkid) REFERENCES gender (id)
However to create the relationship the two columns need to have the same data type. user_info .genderpkid is VARCHAR (10) and user_info.id is int.
The other problem you might encounter is that the insert scripts insert the data into genderpkid column as M or F. Therefore int is not going to work
If you were to use use the values M or F for gender, then you can create a script like:
CREATE TABLE gender (
id VARCHAR (1),
gender VARCHAR (20)
CONSTRAINT gender_pk PRIMARY KEY (id)
);
CREATE TABLE user_info (
id int PRIMARY KEY IDENTITY (1,1),
usr_name VARCHAR (30) NOT NULL,
f_name VARCHAR (30) NOT NULL,
l_name VARCHAR (30),
b_day DATE,
email VARCHAR (120) NOT NULL,
genderId VARCHAR (1) NOT NULL,
CONSTRAINT gender_fk FOREIGN KEY (genderId) REFERENCES gender (id),
);
INSERT INTO gender (id, gender)
VALUES
('F', 'Female'),
('M', 'Male')
INSERT
INTO user_info
( usr_name, f_name, l_name, b_day, genderId, email)
VALUES
('JMAN', 'JOHN', 'DOE', '1990-01-01','M','EX#EMAIL'),
('JAM','JANE', 'DOE', '1995-05-02','F','EX#EMAIL'),
('NMAN','NICK', 'WEBB', '1999-06-22','M','EX#EMAIL'),
('LOBA','LOLA', 'LILLY', '1994-01-08','F','EX#EMAIL'),
('NOTSPMAN','PETER', 'PARKER','1985-11-25','M','EX#EMAIL');
SELECT * FROM user_info;
A better approach could be, to pass the whole phraze (male / female) to the table user_info. The table gender can be used to enforce referential integrity. All your information is then contained in SELECT * FROM user_info
For example:
CREATE TABLE gender (
[name] VARCHAR (20)
CONSTRAINT gender_pk PRIMARY KEY ([name])
);
CREATE TABLE user_info (
id int PRIMARY KEY IDENTITY (1,1),
usr_name VARCHAR (30) NOT NULL,
f_name VARCHAR (30) NOT NULL,
l_name VARCHAR (30),
b_day DATE,
email VARCHAR (120) NOT NULL,
gender VARCHAR (20) NOT NULL,
genderIntrest VARCHAR (20) NOT NULL,
CONSTRAINT gender_fk FOREIGN KEY (gender) REFERENCES gender ([name]),
CONSTRAINT genderIntrest_fk FOREIGN KEY (genderIntrest) REFERENCES gender ([name]),
);
INSERT INTO gender ([name])
VALUES
('Female'),
('Male')
INSERT
INTO user_info
( usr_name, f_name, l_name, b_day, gender, genderIntrest, email)
VALUES
('JMAN', 'JOHN', 'DOE', '1990-01-01','Male','Female', 'EX#EMAIL'),
('JAM','JANE', 'DOE', '1995-05-02','Female','Female', 'EX#EMAIL'),
('NMAN','NICK', 'WEBB', '1999-06-22','Male','Female','EX#EMAIL'),
('LOBA','LOLA', 'LILLY', '1994-01-08','Female','Female','EX#EMAIL'),
('NOTSPMAN','PETER', 'PARKER','1985-11-25','Male','Female','EX#EMAIL');
SELECT * FROM user_info;
You can remove the gender table and let the app that consumes it pass in the data. However for a learning exercises, it's probably better to leave it in