Retrieve NULL value : Null « Data Type « SQL / MySQL

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SQL / MySQL » Data Type » Null 
Retrieve NULL value

/*
mysql> select * from Student;
+-----------+------------+-----------+
| StudentID | first_name | last_name |
+-----------+------------+-----------+
|         1 | John       | Jones     |
|         2 | NULL       | Burton    |
|         3 | Emily      | Scarlett  |
|         4 | Bruce      | Lee       |
|         5 | Anna       | Wolff     |
|         6 | Vic        | Andrews   |
|         7 | NULL       | Alaska    |
+-----------+------------+-----------+
7 rows in set (0.01 sec)

mysql> select * from Student WHERE first_name IS NULL;
+-----------+------------+-----------+
| StudentID | first_name | last_name |
+-----------+------------+-----------+
|         2 | NULL       | Burton    |
|         7 | NULL       | Alaska    |
+-----------+------------+-----------+
2 rows in set (0.02 sec)


*/
Drop table Student;

CREATE TABLE Student (
   StudentID INT NOT NULL PRIMARY KEY,
   first_name      VARCHAR(50),
   last_name      VARCHAR(50NOT NULL
   
)TYPE = InnoDB;


INSERT INTO Student (StudentID,first_name, last_nameVALUES (4,'Bruce', 'Lee');

INSERT INTO Student (StudentID,first_name, last_nameVALUES (1,'John', 'Jones');
INSERT INTO Student (StudentID, last_nameVALUES (2'Burton');
INSERT INTO Student (StudentID, last_nameVALUES (7'Alaska');
INSERT INTO Student (StudentID,first_name, last_nameVALUES (5,'Anna', 'Wolff');
INSERT INTO Student (StudentID,first_name, last_nameVALUES (6,'Vic', 'Andrews');
INSERT INTO Student (StudentID,first_name, last_nameVALUES (3,'Emily', 'Scarlett');

select from Student;

select from Student WHERE first_name IS NULL; 

           
       
Related examples in the same category
1. Concatenate string with NULL value
2. Working with NULL Values
3. Use the IS NULL and IS NOT NULL operators
4. NULL means 'not having a value'
5. Disallowing NULLs
6. Retrieve NOT NULL value
7. List NOT NULL value and order it
8. Select NOT NULL value
9. IS NOT NULL in where clause
10. NULL value in where clause
11. Read NULL value
12. Dealing With NULL Data
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