Let us first create a table −mysql> create table DemoTable778 ( ClientId varchar(100), ClientName varchar(100) ); Query OK, 0 rows affected (1.05 sec)Insert some records in the table using insert command −mysql> insert into DemoTable778 values('J-101', 'John'); Query OK, 1 row affected (0.20 sec) ... Read More

Let us first create a table −mysql> create table DemoTable777 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100), StudentAge int ); Query OK, 0 rows affected (1.34 sec)Insert some records in the table using insert command −mysql> insert into ... Read More

Let’s say you have set column values as unique key and try to insert duplicate values in the table. This will lead to ERROR 1062 (23000): Duplicate entry.Let us first create a table -mysql> create table DemoTable776 (    FirstValue int,    SecondValue int,    unique key(FirstValue, SecondValue) ); Query ... Read More

Let’s say the current date is 2019-08-03. Now, we will see an example and create a table −mysql> create table DemoTable840(DueDate datetime); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable840 values('2019-08-9'); Query OK, 1 row affected (0.10 sec) mysql> ... Read More

To sum, you can use aggregate function SUM(). Let us first create a table −mysql> create table DemoTable850(    Id int,    Price int ); Query OK, 0 rows affected (0.54 sec)Insert some records in the table using insert command −mysql> insert into DemoTable850 values(1, 90); Query OK, 1 row ... Read More

The current date format is ‘YYYY-mm-dd’. To change current date format, you can use date_format().Let us first display the current date −mysql> select curdate();This will produce the following output −+------------+ | curdate() | +------------+ | 2019-08-08 | +------------+ 1 row in set (0.00 sec)Following is the query to change ... Read More

For this, use aggregate function SUM(). Within this method, multiply the row values. Let us first create a table −mysql> create table DemoTable(    ProductQuantity int,    ProductPrice int ); Query OK, 0 rows affected (0.48 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10, ... Read More

For this, use GROUP BY clause along with aggregate function SUM(). Let us first create a table −mysql> create table DemoTable(    Name varchar(100),    Score int ); Query OK, 0 rows affected (0.70 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Adam', 50); Query ... Read More

Let us first create a table −mysql> create table DemoTable(    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    CustomerName varchar(100) ); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(CustomerName) values('Adam Smith'); Query OK, 1 row affected (0.17 sec) ... Read More

For this, you can use CASE statement. Let us first create a table −mysql> create table DemoTable(    Id int,    Value int ); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10, 100); Query OK, 1 row affected ... Read More