SQL String Concatenation in Informix, MySQL and SQL Server

Like selecting the top N rows, syntax for string concatenation is DBMS-specific. The following are examples for Informix, MySQL and SQL Server.

Informix

select name || ' ' || surname

from customer;

MySQL

select concat(name, ' ', surname)
from customer;

Note: the MySQL concat() function can accept any number of arguments.

SQL Server

select name + ' ' + surname

from customer;

SQL Top n Rows in Informix, MySQL and SQL Server

Different dialects of SQL allow you to obtain the first n rows, resulting from a query, in different ways. The following are examples in Informix, SQL Server, and MySQL. Tip: to get the last n rows, simple switch the order by clause (from ascending to descending, or vice versa).

Informix

select first 5 *

from customer;

MySQL

select *

from customer

limit 5;

SQL Server

select top 5 *

from customer;