SELECT (MySQL)

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Versie door Jeroen Strompf (overleg | bijdragen) op 12 dec 2022 om 07:25
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SELECT is such an ubiquitous statement in SQL, that it seems overkill to write even an article about it. However, occasionally I do come across new or suprising aspect of this command:

Multiple columns in a direct statement

A statement like

select concat ("This ", "are ", "four ", "statements");

can also be done like this:

mysql> select "This", "are", "four", "columns";
+------+-----+------+---------+
| This | are | four | columns |
+------+-----+------+---------+
| This | are | four | columns |
+------+-----+------+---------+
1 row in set (0,00 sec)

or even:

mysql> select "This" as c1, "are" as c2, "four" as c3, "columns" as c4;
+------+-----+------+---------+
| c1   | c2  | c3   | c4      |
+------+-----+------+---------+
| This | are | four | columns |
+------+-----+------+---------+
1 row in set (0,00 sec)