Return true or false in a MySQL select if another field contains a string?

To return TRUE or FALSE if another field contains a string, use IF(). Let us first create a table

mysql> 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','Brown');
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable values('David','Miller');
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable values('Adam','Smith');
Query OK, 1 row affected (0.11 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

This will produce the following output −

+-----------+----------+
| FirstName | LastName |
+-----------+----------+
| Chris     | Brown    |
| David     | Miller   |
| Adam      | Smith    |
+-----------+----------+
3 rows in set (0.00 sec)

Following is the query to return true or false in a MySQL select if another field contains a string. Here, we are checking for string “Miller” −

Mysql> select if(LastName=’Miller’,’Yes','No') AS LastName,FirstName from DemoTable;

This will produce the following output −

+----------+-----------+
| LastName | FirstName |
+----------+-----------+
| No       | Chris     |
| Yes      | David     |
| No       | Adam      |   
+----------+-----------+
3 rows in set (0.00 sec)