cannot insert the NULL value into the column - sql

Question

I have been trying to insert data into the database, but it's continuously showing me this error, even though I not writing the name of the column(MemID) in the first fields, rather I am trying to enter it separately like this
create table Member (
MemID VARCHAR(20) PRIMARY KEY,
FullName VARCHAR(50),
email VARCHAR(50),
gender VARCHAR(50),
Contact_Number VARCHAR(50),
Registration_Number VARCHAR(50),
User_S# INT
);
insert into Member (FullName, email, gender, Contact_Number,
Registration_Number, User_S#) values ('Jemmy Joutapaitis',
'jjoutapaitiscf#dailymail.co.uk', 'Male', '86-[phone]',
'3574884734839928', 449);
insert into Member (FullName, email, gender, Contact_Number,
Registration_Number, User_S#) values ('Cleo Glynn', 'cglynncg#i2i.jp',
'Male', '81-[phone]', '5443114970343516', 450);
insert into Member (FullName, email, gender, Contact_Number,
Registration_Number, User_S#) values ('Ivonne Deetlefs',
'ideetlefsch#virginia.edu', 'Female', '86-[phone]',
'3571675846170605', 451);
insert into Member(MemID)
values('Mem0');
insert into Member(MemID)
values('Mem1');
insert into Member(MemID)
values('Mem2');
This code is giving me the error
Cannot insert the value NULL into column 'MemID', table
'master.dbo.Member'; column does not allow nulls. INSERT fails.
But I am inserting MemID column separately.
And also the table which has created above is not showing in the database, is it because of the error or something else?

Answer 1

That's not how inserts work.
When an insert is triggered sql tries to add the row immediately, without waiting for the consequent statements (it's stands true for any dml statements not only insert).
So when your first insert is triggered then sql is trying to put null in MemID as you haven't supplied any MemID in your insert.
Try inserting it in the very first place itself in the insert. Instead of separate statement something like:
insert into Member (MemID, FullName, email, gender, Contact_Number,
Registration_Number, User_S#) values ('Mem0','Jemmy Joutapaitis',
'jjoutapaitiscf#dailymail.co.uk', 'Male', '86-[phone]',
'3574884734839928', 449);
EDIT
With response to your comment , I think Prepared statements is what you're looking for.
Since you're using python you could do prepare your insert statement like:
sql = "insert into Member (MemID, FullName, email, gender, Contact_Number,
Registration_Number, User_S#) values (%s,'Jemmy Joutapaitis',
'jjoutapaitiscf#dailymail.co.uk', 'Male', '86-[phone]',
'3574884734839928', 449);"
sql = sql.format(self.db_scan_table)
//whenever you've memid ready use.
self.cursor.execute(sql, ('Mem01'))

Answer 2

Define an AUTO_INCREMENT column to generate ID values for you:
CREATE TABLE Member (
MemID INT AUTO_INCREMENT PRIMARY KEY,
-- ...
);
If this isn't practical because you need some kind of particular string definition for these then your only option is to supply it as part of the initial INSERT call. You have a constraint here, the PRIMARY KEY value must not be NULL.

Answer 3

should be able to using the query below. identify the next number
insert into member(memid,......)
values ( 'MEM' + cast((select count(1) from member)+1 as varchar(100)),... )
if you want to start with 1 then + 1
otherwise remove + 1
insert into member(memid,......)
values ( 'MEM' + cast((select count(1) from member) as varchar(100)),... )