To set NULL values, set the type as NULL as in the below syntax −yourColumnName dataType NULL;Let us first create a table −mysql> create table DemoTable759 (    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    FirstName varchar(100) NULL ); Query OK, 0 rows affected (0.72 sec)Insert some records in the table using insert command −mysql> insert into DemoTable759(FirstName) values('John'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable759(FirstName) values(NULL); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable759(FirstName) values('Carol'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable759(FirstName) values(NULL); Query OK, 1 row ... Read More

To set the default value, use the DEFAULT keyword.Let us first create a table −mysql> create table DemoTable758 (    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    FirstName varchar(100) ); Query OK, 0 rows affected (0.66 sec)Following is the query to set default value for a column −mysql> alter table DemoTable758 add column Colors ENUM('RED', 'GREEN', 'BLUE', 'ORANGE', 'YELLOW') DEFAULT 'YELLOW'; Query OK, 0 rows affected (0.44 sec) Records: 0 Duplicates: 0 Warnings: 0Let us check the description of table once again −mysql> desc DemoTable758;This will produce the following output -+-----------+----------------------------------------------+------+-----+---------+----------------+ | Field     | Type     ... Read More

Let’s say you have a VARCHAR column in a table with values are strings and the numbers are on the right side. For example −John1023 Carol9871 David9098Now, consider you want to order by on the basis of these right-side numbers in the entire column. For this, use ORDER BY RIGHT.Let us first create a table −mysql> create table DemoTable757 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, ClientId varchar(100) ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command −mysql> insert into DemoTable757(ClientId) values('John1023'); Query OK, 1 row ... Read More

Let us first create a table −mysql> create table DemoTable756 (    Value1 int,    Value2 int,    Value3 int ); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable756 values(10, 20, 14); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable756 values(20, 34, 17); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable756 values(200, 134, 789); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable756 values(139, 98, 99); Query OK, 1 row affected (0.17 sec)Display all records from the table using select statement ... Read More

For this, use alias on HAVING clause.Let us first create a table −mysql> create table DemoTable755 (    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    Score1 int,    Score2 int ); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable755(Score1, Score2) values(30, 23); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable755(Score1, Score2) values(50, 60); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable755(Score1, Score2) values(89, 90); Query OK, 1 row affected (0.29 sec) mysql> insert into DemoTable755(Score1, Score2) values(99, 99); Query OK, 1 row ... Read More

To return only the distinct values, use GROUP BY clause.Let us first create a table −mysql> create table DemoTable754 (ProductPrice int); Query OK, 0 rows affected (0.48 sec)Insert some records in the table using insert command −mysql> insert into DemoTable754 values(200); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable754 values(500); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable754 values(200); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable754 values(500); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable754 values(800); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable754 ... Read More

To fetch only the month part, use DATE_FORMAT().Let us first create a table −mysql> create table DemoTable753 (DueDate datetime); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable753 values('2019-06-21'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable753 values('2019-01-31'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable753 values('2018-12-01'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable753 values('2016-11-11'); Query OK, 1 row affected (0.23 sec)Display all records from the table using select statement −mysql> select *from DemoTable753;This will produce the following output -+---------------------+ ... Read More

To implement IN() for custom ordering, use ORDER BY CASE.Let us first create a table −mysql> create table DemoTable752 (    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    Name varchar(100) ); Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable752(Name) values('John'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable752(Name) values('Carol'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable752(Name) values('Bob'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable752(Name) values('Mike'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable752(Name) values('Sam'); ... Read More

For this, you can use GROUP BY HAVING clause.Let us first create a table −mysql> create table DemoTable751 (    StudentName varchar(100),    SubjectName varchar(100) ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable751 values('John', 'MySQL'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable751 values('John', 'MongoDB'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable751 values('Sam', 'MySQL'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable751 values('Carol', 'Java'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable751 values('David', 'MySQL'); ... Read More

Let’s say some of the columns values in a table has a specific keyword and you want only those records. For this, use the LIKE operator.Let us first see an example and create a table −mysql> create table DemoTable750 (Title varchar(200)); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command −mysql> insert into DemoTable750 values('Java and MongoDB, MySQL'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable750 values('MySQL, SQL Server'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable750 values('PL/SQL, Python, MongoDB'); Query OK, 1 row affected (0.14 sec) mysql> ... Read More