title: multiply two varchars in sql
body: <p>This what I have tried but it is giving errors:</p>
  
  <pre><code>MariaDB [test]&gt; create table table1 (length varchar, breadth varchar);                                                             
  ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ' breadth varchar)' at line 1
  MariaDB [test]&gt; create table table1 (length varchar(20), breadth varchar(20));                                                         
  Query OK, 0 rows affected (0.06 sec)
  MariaDB [test]&gt; insert into table1 (length, breadth) values ('12','11');                                                                                                                               
  Query OK, 1 row affected (0.05 sec)                                                                                                                                                                    
  
  MariaDB [test]&gt; select * from table1;                                                                                                                                                                  
  +--------+---------+                                                                                                                                                                                   
  | length | breadth |                                                                                                                                                                                   
  +--------+---------+                                                                                                                                                                                   
  | 12     | 11      |                                                                                                                                                                                   
  +--------+---------+                                                                                                                                                                                   
  1 row in set (0.02 sec)                                                                                                                                                                                                                                                                                                                                                                                   
  MariaDB [test]&gt; select convert (int, length)*convert(int, breadth) as T from table1;                                                                                                                   
  ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'int, length)*convert(int, breadth) as T fr
  om table1' at line 1                                                                                                                                                                                   
  MariaDB [test]&gt; select convert(int, length)*convert(int, breadth) as T from table1;                                                                                                                    
  ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'int, length)*convert(int, breadth) as T fr
  om table1' at line 1                                                                                                                                                                                   
  </code></pre>