To add a set of elements in a single cell, use the concept of JSON. Let us first create a table −mysql> create table DemoTable1828      (      EmployeeId int,      EmployeeRecords JSON      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1828 values(1, '[{"EmployeeName":"Chris", "EmployeeAge":29}, {"EmployeeName":"David", "EmployeeAge":27}]'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1828 values(2, '[{"EmployeeName":"John", "EmployeeAge":36}, {"EmployeeName":"Mike", "EmployeeAge":32}]'); Query OK, 1 row affected (0.00 sec)Display all records from the table using select statement −mysql> select * from DemoTable1828; This ... Read More

To check for NULL or empty variable, use the IF condition. Let us create a stored procedure −mysql> delimiter // mysql> create procedure checkingForNullDemo(Name varchar(20))      begin      if Name is NULL OR Name='' then      select 'Adam Smith';      else      select Name;      end if ;      end      // Query OK, 0 rows affected (0.00 sec) mysql> delimiter ;Case 1When NULL is passed. Call the stored procedure using call commandmysql> call checkingForNullDemo(NULL);This will produce the following output −+------------+ | Adam Smith | +------------+ | Adam Smith | +------------+ 1 ... Read More

Let us create a stored procedure. Here, we are calculating amount*quantity i.e. implementing mathematical operations −mysql> delimiter // mysql> create procedure calculation_proc(amount int,quantity int)      begin      select amount,quantity,(amount*quantity) as Total;      end      // Query OK, 0 rows affected (0.00 sec) mysql> delimiter ;Now you can call a stored procedure using call command −mysql> call calculation_proc(250,3);This will produce the following output −+--------+----------+-------+ | amount | quantity | Total | +--------+----------+-------+ |    250 |        3 |   750 | +--------+----------+-------+ 1 row in set (0.00 sec) Query OK, 0 rows affected (0.00 sec)

To search for ^ character, use the LIKE operator as in the below syntax −select table_schema, table_name, column_name  from information_schema.columns  where column_name like '%^%';Let us first create a table −mysql> create table DemoTable1826      (      `^` varchar(20),      Name varchar(20),      `^Age` int      ); Query OK, 0 rows affected (0.00 sec)Here is the query to search for ^ character in a MySQL tablemysql> select table_schema, table_name, column_name      from information_schema.columns      where column_name like '%^%';This will produce the following output −+--------------+---------------+-------------+ | TABLE_SCHEMA | TABLE_NAME    | COLUMN_NAME | +--------------+---------------+-------------+ | ... Read More

For this, you can use IS NOT NULL property. Let us first create a table −mysql> create table DemoTable1      (      DueDate date      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1 values('2019-09-10'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1 values(NULL); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1 values('2019-11-10'); Query OK, 1 row affected (0.00 sec)Display all records from the table using select statement −mysql> select * from DemoTable1; This will produce the following output −+------------+ ... Read More

To increase precision with division, use MySQL CAST(). Let us first create a table −mysql> create table DemoTable1823      (      Value int      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1823 values(1); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1823 values(2); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1823 values(3); Query OK, 1 row affected (0.00 sec)Display all records from the table using select statement −mysql> select * from DemoTable1823;This will produce the following output −+-------+ | Value ... Read More

Let us first create a table −mysql> create table DemoTable1822      (      Amount int,      DueDate date      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1822 values(1000, '2019-10-11'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1822 values(500, '2019-11-30'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1822 values(700, '2018-11-30'); Query OK, 1 row affected (0.00 sec)Display all records from the table using select statement −mysql> select * from DemoTable1822;This will produce the following output −+--------+------------+ | Amount | ... Read More

No, the query won’t work. Let’s create the same scenario and check the error −mysql> create table DemoTable1821      (      Id int,      FirstName varchar,      LastName varchar      ); ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ', LastName varchar )' at line 4To remove the above error, you need to give the size of varchar(10). Let us first create a table −mysql> create table DemoTable1821      (      Id int, ... Read More

For this, you can use DATE_FORMAT(). Let us first create a table −mysql> create table DemoTable1820      (      AdmissionDate varchar(20)      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1820 values('20/10/2019'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1820 values('19/12/2018'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1820 values('16/04/2017'); Query OK, 1 row affected (0.00 sec)Display all records from the table using select statement −mysql> select * from DemoTable1820;This will produce the following output −+---------------+ | AdmissionDate | +---------------+ ... Read More

For this, you can use COUNT() along with GROUP BY MONTH(). To match with the current date, use CURRENT_DATE(). The current date is as follows −mysql> select curdate() ; +------------+ | curdate()  | +------------+ | 2019-11-30 | +------------+ 1 row in set (0.00 sec)Let us first create a table −mysql> create table DemoTable1819      (      Name varchar(20),      RegisteringDate datetime      ); Query OK, 0 rows affected (0.00 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1819 values('Chris', '2019-11-29 12:30:34'); Query OK, 1 row affected (0.00 sec) mysql> insert into DemoTable1819 ... Read More