Concatenate

Sometimes it is necessary to combine together (concatenate) the results from several different fields. Each database provides a way to do this:

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

The syntax for CONCAT( ) is as follows:

CONCAT(str1, str2, str3, ...): Concatenate str1, str2, str3, and any other strings together. Please note the Oracle CONCAT( ) function only allows two arguments -- only two strings can be put together at a time using this function. However, it is possible to concatenate more than two strings at a time in Oracle using '||'.

Let's look at some examples. Assume we have the following table:

Table Geography

region_namestore_name
EastBoston
EastNew York
WestLos Angeles
WestSan Diego

Example 1:

MySQL/Oracle:
SELECT CONCAT(region_name,store_name) FROM Geography
WHERE store_name = 'Boston';

Result:

'EastBoston'

Example 2:

Oracle:
SELECT region_name || ' ' || store_name FROM Geography
WHERE store_name = 'Boston';

Result:

'East Boston'

Example 3:

SQL Server:
SELECT region_name + ' ' + store_name FROM Geography
WHERE store_name = 'Boston';

Result:

'East Boston'

Next: SQL SUBSTRING