To update a field if it is null, use IS NULL property along with the UPDATE command. Let us first create a table −mysql> create table DemoTable (    StudentScore int ); Query OK, 0 rows affected (0.47 sec)Insert some records in the table using insert command −mysql> insert into ... Read More

To insert values from the first table to another table using two SELECT statements, use SUBQUERY. This will allow you to use only a single MySQL query to get the result in the second table. Let us first create a table −mysql> create table DemoTable1 (    Name varchar(100),   ... Read More

For this, let us first create a table −mysql> create table DemoTable (    Message text ); Query OK, 0 rows affected (1.15 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.43 sec) mysql> insert into DemoTable values('Bye'); Query ... Read More

To set the default value in MySQL, you need to use the DEFAULT keyword. Let us first create a table −mysql> create table DemoTable (    ClientCountryName varchar(100) DEFAULT 'NONE' ); Query OK, 0 rows affected (0.65 sec)We have set DEFAULT above for values not entered while insertion. Now, let ... Read More

To fetch number of characters from the left of the string, use the LEFT method in MySQL. Let us first create a table −mysql> create table DemoTable (    Name varchar(100) ); Query OK, 0 rows affected (6.58 sec)Insert some records in the table using insert command −mysql> insert into ... Read More

Yes, we can use the SELECT NULL statement in a MySQL query. Let us first create a table −mysql> create table DemoTable (    Name varchar(100) ); Query OK, 0 rows affected (0.49 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 ... Read More

For this, use ORDER BY DESC with the LIMIT clause. The ORDER BY DESC order in descending order where LIMIT sets the number of records you want. Here, we will set LIMIT 1 since we want only a single record. Let us first create a table −mysql> create table DemoTable ... Read More

Let us first create a table −mysql> create table DemoTable (    Score int ); Query OK, 0 rows affected (0.65 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(45); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(29); Query OK, 1 ... Read More

To return TRUE or FALSE if another field contains a string, use IF(). Let us first create a tablemysql> create table DemoTable (    FirstName varchar(100),    LastName varchar(100) ); Query OK, 0 rows affected (1.28 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', ... Read More

Since the column wherein you want to get the value more than a particular value is VARCHAR, use the CAST() function. For example, to fetch the value more than 999 from a column with varchar values.Let us first create a table −mysql> create table DemoTable (    Value varchar(100) ); ... Read More