SQL Basics | Functions | Concatenate

Sometimes you need to combine data from different fields. Each database has a way to achieve this.

  • MySQL: CONCAT()
  • Oracle: CONCAT(), ||
  • SQL Server: +

Concatenate syntax

CONCAT() is used as follows.

CONCAT(string1, string2, string3, ...)

It combines string1, string2, string3, and so on. Note that Oracle’s CONCAT() accepts two parameters. In other words, it can combine only two strings at a time. To combine multiple strings at once, use ||.

Concatenate example

For example, suppose you have the following table.

geography table

region_name store_name
East Boston
East New York
West Los Angeles
West San Diego

Example 1

MySQL / Oracle:

SELECT CONCAT(region_name, store_name) FROM geography
WHERE store_name = 'Boston';

The result is as follows.

'EastBoston'

Example 2

Oracle:

SELECT region_name || ' ' || store_name FROM geography
WHERE store_name = 'Boston';

The result is as follows.

'East Boston'

Example 3

SQL Server:

SELECT region_name + ' ' + store_name FROM geography
WHERE store_name = 'Boston';

The result is as follows.

'East Boston'