Database Reference
In-Depth Information
▼
Analysis
The
RTrim()
function trims all spaces from the right of a value. By using
RTrim()
, the individual columns are all trimmed properly.
Note
The
Trim()
Functions In addition to
RTrim()
(which, as just seen, trims the right
side of a string), MariaDB supports the use of
LTrim()
(which trims the left side of a
string), and
Trim()
(which trims both the right and left).
The
SELECT
statement used to concatenate the address field works well, as seen
in the previous output. But what is the name of this new calculated column?
Well, the truth is, it has no name; it is simply a value. Although this can be fine
if you are just looking at the results in a SQL query tool, an unnamed column
cannot be used within a client application because the client has no way to
refer to that column.
To solve this problem, SQL supports column aliases. An
alias
is just that, an
alternative name for a field or value. Aliases are assigned with the
AS
keyword.
Take a look at the following
SELECT
statement:
▼
Input
SELECT Concat(RTrim(vend_name), ' (', RTrim(vend_country), ')') AS vend_
title
FROM vendors
ORDER BY vend_title;
▼
Output
+-------------------------+
| vend_title |
+-------------------------+
| ACME (USA) |
| Anvils R Us (USA) |
| Furball Inc. (USA) |
| Jet Set (England) |
| Jouets Et Ours (France) |
| LT Supplies (USA) |
+-------------------------+
