Quiz — 16_chapitre5_mode_commande_drop_column.pdf

Question 1 sur 10 20:00

[{"id":53057,"question":"Quelle commande SQL permet de supprimer une colonne d'une table ?","option_a":"ALTER TABLE ... DROP COLUMN","option_b":"DELETE COLUMN","option_c":"REMOVE COLUMN","option_d":"DROP COLUMN","option_e":"","option_f":"","bonne_reponse":"a","explication":"La commande correcte est \u003Cstrong\u003EALTER TABLE ... DROP COLUMN\u003C\/strong\u003E, qui modifie la structure de la table pour supprimer une colonne.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"ALTER TABLE ... DROP COLUMN\", \"b\": \"DELETE COLUMN\", \"c\": \"REMOVE ","_debug_options_count":4},{"id":53058,"question":"La commande DROP TABLE supprime uniquement la structure de la table, pas ses données.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"La commande DROP TABLE supprime \u003Cstrong\u003Eà la fois la structure et toutes les données\u003C\/strong\u003E de la table.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":53059,"question":"Quelle syntaxe est correcte pour supprimer une colonne nommée 'age' de la table 'utilisateurs' ?","option_a":"DROP COLUMN age FROM utilisateurs","option_b":"ALTER TABLE utilisateurs DROP COLUMN age","option_c":"DELETE COLUMN age FROM utilisateurs","option_d":"REMOVE age FROM utilisateurs","option_e":"","option_f":"","bonne_reponse":"b","explication":"La syntaxe correcte est \u003Cstrong\u003EALTER TABLE utilisateurs DROP COLUMN age\u003C\/strong\u003E.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"DROP COLUMN age FROM utilisateurs\", \"b\": \"ALTER TABLE utilisateur","_debug_options_count":4},{"id":53060,"question":"Peut-on utiliser une transaction pour annuler une commande DROP TABLE ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Oui, si la commande est exécutée dans une transaction, vous pouvez utiliser \u003Cstrong\u003EROLLBACK\u003C\/strong\u003E pour annuler les modifications.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":53061,"question":"Quelle commande permet de supprimer une table nommée 'clients' ?","option_a":"DELETE TABLE clients","option_b":"DROP TABLE clients","option_c":"REMOVE TABLE clients","option_d":"ALTER TABLE clients DROP","option_e":"","option_f":"","bonne_reponse":"b","explication":"La commande correcte est \u003Cstrong\u003EDROP TABLE clients\u003C\/strong\u003E.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"DELETE TABLE clients\", \"b\": \"DROP TABLE clients\", \"c\": \"REMOVE TA","_debug_options_count":4},{"id":53062,"question":"Quelle est la conséquence principale de supprimer une colonne utilisée par une clé étrangère ?","option_a":"Aucune conséquence","option_b":"Erreur dans les requêtes utilisant cette clé","option_c":"La clé étrangère est automatiquement recréée","option_d":"La table est supprimée","option_e":"","option_f":"","bonne_reponse":"b","explication":"Supprimer une colonne utilisée par une clé étrangère peut entraîner des \u003Cstrong\u003Eerreurs dans les requêtes\u003C\/strong\u003E qui l'utilisent.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Aucune conséquence\", \"b\": \"Erreur dans les requêtes utilisant c","_debug_options_count":4},{"id":53063,"question":"La commande DROP COLUMN peut être utilisée pour supprimer plusieurs colonnes en une seule requête.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Non, vous devez exécuter une commande DROP COLUMN \u003Cstrong\u003Epar colonne\u003C\/strong\u003E à supprimer.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":53064,"question":"Quelle commande permet de vérifier la structure d'une table avant de supprimer une colonne ?","option_a":"SHOW TABLE","option_b":"DESCRIBE table_name","option_c":"VIEW TABLE","option_d":"CHECK TABLE","option_e":"","option_f":"","bonne_reponse":"b","explication":"La commande \u003Cstrong\u003EDESCRIBE table_name\u003C\/strong\u003E permet de visualiser la structure d'une table.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"SHOW TABLE\", \"b\": \"DESCRIBE table_name\", \"c\": \"VIEW TABLE\", \"d\": ","_debug_options_count":4},{"id":53065,"question":"Quelle est la syntaxe correcte pour supprimer une table nommée 'produits' avec une condition de sécurité ?","option_a":"DROP TABLE produits IF EXISTS","option_b":"DROP TABLE produits","option_c":"DELETE TABLE produits IF EXISTS","option_d":"REMOVE TABLE produits IF EXISTS","option_e":"","option_f":"","bonne_reponse":"a","explication":"La syntaxe \u003Cstrong\u003EDROP TABLE produits IF EXISTS\u003C\/strong\u003E permet de supprimer la table uniquement si elle existe, évitant ainsi une erreur.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"DROP TABLE produits IF EXISTS\", \"b\": \"DROP TABLE produits\", \"c\": ","_debug_options_count":4},{"id":53066,"question":"Quelle commande permet de supprimer une table et de vérifier si elle existe avant l'opération ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Oui, la commande \u003Cstrong\u003EDROP TABLE IF EXISTS\u003C\/strong\u003E permet de supprimer une table uniquement si elle existe, évitant ainsi une erreur.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4}]