Update all varchar column rows to display values before slash in MySQL?

For this, use UPDATE command along with SUBSTRING_INDEX(). Let us first create a table −

mysql> create table demo69
−> (
−> name varchar(40)
−> );
Query OK, 0 rows affected (5.04 sec)

Insert some records into the table with the help of insert command −

mysql> insert into demo69 values('John/Smith');
Query OK, 1 row affected (0.83 sec)

mysql> insert into demo69 values('David/Miller');
Query OK, 1 row affected (0.23 sec)

mysql> insert into demo69 values('Chris/Brown');
Query OK, 1 row affected (0.40 sec)

mysql> insert into demo69 values('Carol/Taylor');
Query OK, 1 row affected (0.36 sec)

Display records from the table using select statement −

mysql> select *from demo69;

This will produce the following output −

+--------------+
| name         |
+--------------+
| John/Smith   |
| David/Miller |
| Chris/Brown  |
| Carol/Taylor |
+--------------+
4 rows in set (0.03 sec)

Following is the query to update all varchar column rows −

mysql> update demo69
−> set name=substring_index(name,'/',1);
Query OK, 4 rows affected (0.13 sec)
Rows matched: 4 Changed: 4 Warnings: 0

Display records from the table using select statement −

mysql> select *from demo69;

This will produce the following output −

+-------+
| name  |
+-------+
| John  |
| David |
| Chris |
| Carol |
+-------+
4 rows in set (0.00 sec)