How to get the longest VarChar length in MySQL?

To get the longest varchar length, you need to use CHAR_LENGTH().

The syntax is as follows

SELECT Max(CHAR_LENGTH(yourColumnName)) AS anyAliasName FROM yourTableName;

To understand the above syntax, let us create a table. The query to create a table is as follows

mysql> create table CharLengthDemo
   - > (
   - > Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   - > Sentence varchar(255)
   - > );
Query OK, 0 rows affected (0.60 sec)

Insert some records in the table using insert command.

The query is as follows

mysql> insert into CharLengthDemo(Sentence) values('Java is an object oriented programming language'
- > );
Query OK, 1 row affected (0.45 sec)
mysql> insert into CharLengthDemo(Sentence) values('MySQL is a Relational Database Management System');
Query OK, 1 row affected (0.26 sec)
mysql> insert into CharLengthDemo(Sentence) values('JSP uses Java Programming Language');
Query OK, 1 row affected (0.24 sec)
mysql> insert into CharLengthDemo(Sentence) values('Object is a root class in java');
Query OK, 1 row affected (0.12 sec)

Display all records from the table using select statement.

The query is as follows

mysql> select *from CharLengthDemo;

The following is the output

+----+--------------------------------------------------+
| Id | Sentence                                         |
+----+--------------------------------------------------+
|  1 | Java is an object oriented programming language  |
|  2 | MySQL is a Relational Database Management System |
|  3 | JSP uses Java Programming Language               |
|  4 | Object is a root class in java                   |
+----+--------------------------------------------------+
4 rows in set (0.00 sec)

Here is the query to get the longest varchar length

mysql> SELECT Max(CHAR_LENGTH(Sentence)) AS MAXLENGTH FROM CharLengthDemo;

The following is the output displaying the value with the longest varchar length

+-----------+
| MAXLENGTH |
+-----------+
|        48 |
+-----------+
1 row in set (0.00 sec)