How to replace a character in a MySQL table?

To replace only a single character, use REPLACE() in MySQL. Let us first create a table −

mysql> create table DemoTable
   -> (
   -> Name varchar(20)
   -> );
Query OK, 0 rows affected (0.69 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values('John Smitk');
Query OK, 1 row affected (0.09 sec)
mysql> insert into DemoTable values('David Miller');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable values('Adam Smitk');
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 −

+--------------+
| Name         |
+--------------+
| John Smitk   |
| David Miller |
| Adam Smitk   |
+--------------+
3 rows in set (0.00 sec)

Here is the query to replace a character −

mysql> update DemoTable
   -> set Name=replace(Name,'k','h');
Query OK, 2 rows affected (0.13 sec)
Rows matched: 3 Changed: 2 Warnings: 0

Let us check the table records once again −

mysql> select *from DemoTable;

This will produce the following output −

+--------------+
| Name         |
+--------------+
| John Smith   |
| David Miller |
| Adam Smith   |
+--------------+
3 rows in set (0.00 sec)