A query FROM Staff, Districts with no join condition returns 90,000 rows, although there are 3,000 staff and 30 districts. What happened?
Une requête FROM Staff, Districts sans condition de jointure renvoie 90 000 lignes, alors qu'il y a 3 000 agents et 30 districts. Que s'est-il passé ?
Answers
AThe database duplicated its data because of a hardware fault in the diskLa base a dupliqué ses données à cause d'une panne matérielle du disque
BA Cartesian product: every staff row was paired with every districtUn produit cartésien : chaque agent a été associé à chaque district
CEach staff member works in 30 districtsChaque agent travaille dans 30 districts
DThe query returned only the first pageLa requête n'a renvoyé que la première page
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