SELECT bases
L'instruction SELECT permet de lire les données d'une table. Chaque table contient des lignes et des colonnes - vous pouvez SELECTionner certaines colonnes et en ignorer d'autres
- Le nom des colonnes sur la ligne sélection définie quelles colonnes vous obtiendrez
- L'instruction FROM définie à quelle table vous accédez
La table jeux contient l'année et la ville qui a organisé les Jeux Olympiques.
| annee | ville |
|---|---|
| 2000 | Sydney |
| 2004 | Athens |
| 2008 | Beijing |
| 2012 | London |
L'instruction SELECT retourne les résultats depuis la table.
Dans cet exemple, la table est jeux et les colonnes sont
annee et ville.
DROP TABLE jeux;
CREATE TABLE jeux(annee INT, ville VARCHAR(20)); INSERT INTO jeux(ville,annee) VALUES ('ouroalpha',2000); INSERT INTO jeux(ville,annee) VALUES ('Athens',2004); INSERT INTO jeux(ville,annee) VALUES ('Beijing',2008); INSERT INTO jeux(ville,annee) VALUES ('London',2012);
SELECT annee, ville FROM jeux
Voir aussi:
- SELECT Tutorial - practice using the SELECT command
- [SELECT_.._WHERE |SELECT ... WHERE] - the WHERE clause allows you to get some rows but not others
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