MySQL-এ LEFT() ফাংশন ব্যবহার করে প্রথম অক্ষর চেক করা যায়। প্রথমে একটি টেবিল তৈরি করি:
mysql> create table DemoTable1428 (
-> EmployeeId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> EmployeeName varchar(20)
-> );
Query OK, 0 rows affected (1.05 sec)
রেকর্ড ইনসার্ট করি:
mysql> insert into DemoTable1428(EmployeeName) values('Chris Brown');
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable1428(EmployeeName) values('Bob Brown');
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable1428(EmployeeName) values('John Smith');
Query OK, 1 row affected (0.23 sec)
mysql> insert into DemoTable1428(EmployeeName) values('David Miller');
Query OK, 1 row affected (0.18 sec)
mysql> insert into DemoTable1428(EmployeeName) values('John Doe');
Query OK, 1 row affected (0.22 sec)
mysql> insert into DemoTable1428(EmployeeName) values('Carol Johnson');
Query OK, 1 row affected (0.16 sec)
সব রেকর্ড দেখি:
mysql> select * from DemoTable1428;
আউটপুট:
+------------+---------------+ | EmployeeId | EmployeeName | +------------+---------------+ | 1 | Chris Brown | | 2 | Bob Brown | | 3 | John Smith | | 4 | David Miller | | 5 | John Doe | | 6 | Carol Johnson | +------------+---------------+ 6 rows in set (0.00 sec)
প্রথম অক্ষর 'J' দিয়ে ফিল্টার করার কোয়েরি:
mysql> select * from DemoTable1428 where left(EmployeeName,1)='J';
আউটপুট:
+------------+--------------+ | EmployeeId | EmployeeName | +------------+--------------+ | 3 | John Smith | | 5 | John Doe | +------------+--------------+ 2 rows in set (0.00 sec)
বিকল্প: SUBSTRING(EmployeeName,1,1)='J' বা EmployeeName LIKE 'J%' ও ব্যবহার করা যায়।