How to handle null from a text file in Mysql if the data type is Char(1)? - mysql

Question

This is my first time trying Mysql. I created a table using the following command.
CREATE TABLE IF NOT EXISTS `COMPANY`.`EMPLOYEE` (
`Fname` VARCHAR(15) NOT NULL,
`Minit` CHAR NULL,
`Lname` VARCHAR(15) NOT NULL,
`Ssn` CHAR(9) NOT NULL,
`Bdate` DATE NULL,
`Address` VARCHAR(30) NULL,
`Sex` CHAR NULL,
`Salary` DECIMAL(10,2),
`Super_ssn` CHAR(9) NULL,
`Dno` INT NOT NULL,
PRIMARY KEY (`Ssn`));
And I was trying to fill the table using the command below:
LOAD DATA
INFILE 'C:\\ProgramData\\MySQL\\MySQL Server 8.0\\Uploads\\EMPLOYEE.txt'
INTO TABLE employee
FIELDS TERMINATED BY ', '
OPTIONALLY ENCLOSED BY ''''
LINES TERMINATED BY '\n'
(Fname,Minit,Lname,Ssn,#var2,Address,Sex,Salary,Super_ssn,Dno)
SET Bdate=str_to_date(#var2,'%d-%b-%Y');
And this is my text file
'James', 'E', 'Borg', '888665555', '10-NOV-1927', '450 Stone,Houston,TX', 'M', 55000, null, 1
'Franklin',null, 'Wong', '333445555', '08-DEC-1945', '638 Voss,Houston,TX', 'M', 40000, '888665555', 5
I am getting an error saying:
Error Code: 1406. Data too long for column 'Minit' at row 2
How do I solve this?

Answer 1

The problem is that you used optionally in the enclosed by setting. If the enclosing character is required, it will treat null with no quotes around it as a NULL value. Otherwise, it interprets it as the literal string "null", and requires you to use \N to specify a null value.
You could use an intermediate variable to translate it yourself.
LOAD DATA
INFILE 'C:\\ProgramData\\MySQL\\MySQL Server 8.0\\Uploads\\EMPLOYEE.txt'
INTO TABLE employee
FIELDS TERMINATED BY ', '
OPTIONALLY ENCLOSED BY ''''
LINES TERMINATED BY '\n'
(Fname,#Minit,Lname,Ssn,#var2,Address,Sex,Salary,Super_ssn,Dno)
SET Bdate=str_to_date(#var2,'%d-%b-%Y'), Minit = NULLIF(#Minit, 'null')