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Sous-Interrogations - sql oracle

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Sous-Interrogations - sql oracle

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  • DOWNLOAD THAT BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book that can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer that is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story That Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money That the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths that Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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  • DOWNLOAD THAT BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book that can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer that is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story That Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money That the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths that Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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  • DOWNLOAD THAT BOOKS INTO AVAILABLE FORMAT (2019 Update) ......................................................................................................................... ......................................................................................................................... Download Full PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download Full doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download PDF EBOOK here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download EPUB Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... Download doc Ebook here { http://bit.ly/2m6jJ5M } ......................................................................................................................... ......................................................................................................................... ................................................................................................................................... eBook is an electronic version of a traditional print book that can be read by using a personal computer or by using an eBook reader. (An eBook reader can be a software application for use on a computer such as Microsoft's free Reader application, or a book-sized computer that is used solely as a reading device such as Nuvomedia's Rocket eBook.) Users can purchase an eBook on diskette or CD, but the most popular method of getting an eBook is to purchase a downloadable file of the eBook (or other reading material) from a Web site (such as Barnes and Noble) to be read from the user's computer or reading device. Generally, an eBook can be downloaded in five minutes or less ......................................................................................................................... .............. Browse by Genre Available eBooks .............................................................................................................................. Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, ......................................................................................................................... ......................................................................................................................... .....BEST SELLER FOR EBOOK RECOMMEND............................................................. ......................................................................................................................... Blowout: Corrupted Democracy, Rogue State Russia, and the Richest, Most Destructive Industry on Earth,-- The Ride of a Lifetime: Lessons Learned from 15 Years as CEO of the Walt Disney Company,-- Call Sign Chaos: Learning to Lead,-- StrengthsFinder 2.0,-- Stillness Is the Key,-- She Said: Breaking the Sexual Harassment Story That Helped Ignite a Movement,-- Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones,-- Everything Is Figureoutable,-- What It Takes: Lessons in the Pursuit of Excellence,-- Rich Dad Poor Dad: What the Rich Teach Their Kids About Money That the Poor and Middle Class Do Not!,-- The Total Money Makeover: Classic Edition: A Proven Plan for Financial Fitness,-- Shut Up and Listen!: Hard Business Truths that Will Help You Succeed, ......................................................................................................................... .........................................................................................................................
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Sous-Interrogations - sql oracle

  1. 1. Copyright © Oracle Corporation, 1997. Tous droits réservés. 77 Sous-Interrogations www.TelechargerCours.com
  2. 2. 7-2 Copyright © Oracle Corporation, 1997. Tous droits réservés. Objectifs A la fin de ce chapitre, vous saurez :A la fin de ce chapitre, vous saurez : • Décrire les types de problèmes que les sous-interrogations peuvent résoudre • Définir des sous-interrogations • Enumérer les types de sous- interrogations • Ecrire des sous-interrogations mono- ligne et multi-ligne www.TelechargerCours.com
  3. 3. 7-3 Copyright © Oracle Corporation, 1997. Tous droits réservés. Définition Une Sous-interrogation est un ordre SELECTUne Sous-interrogation est un ordre SELECT imbriqué dans une clause d’un autre ordreimbriqué dans une clause d’un autre ordre SELECT .SELECT . Elles permettent de sélectionner des lignes d’uneElles permettent de sélectionner des lignes d’une table lorsque la condition dépend des donnéestable lorsque la condition dépend des données de la table elle-même .de la table elle-même . Peuvent être placées dans les clauses SQLPeuvent être placées dans les clauses SQL suivantes :suivantes : WHEREWHERE HAVINGHAVING FROMFROM www.TelechargerCours.com
  4. 4. 7-4 Copyright © Oracle Corporation, 1997. Tous droits réservés. Utilisation d'une Sous-Interrogation pour Résoudre un Problème "Qui a un salaire supérieur à celui de Jones ?""Qui a un salaire supérieur à celui de Jones ?" "Quel employé a un salaire supérieur à celui de Jones ?" Requête principale ?? "Quel est le salaire de Jones ?" ?? sous-interrogation www.TelechargerCours.com
  5. 5. 7-5 Copyright © Oracle Corporation, 1997. Tous droits réservés. Sous-Interrogations • La sous-interrogation (requête interne) est exécutée une fois avant la requête principale. • Le résultat de la sous-interrogation est utilisé par la requête principale (externe). SELECT select_list FROM table WHERE expr operator (SELECT select_list FROM table); www.TelechargerCours.com
  6. 6. 7-6 Copyright © Oracle Corporation, 1997. Tous droits réservés. 2975 SQL> SELECT ename 2 FROM emp 3 WHERE sal > 4 (SELECT sal 5 FROM emp 6 WHERE empno=7566); Utilisation d'une Sous-Interrogation ENAME ---------- KING FORD SCOTT ENAME ---------- KING FORD SCOTT www.TelechargerCours.com
  7. 7. 7-7 Copyright © Oracle Corporation, 1997. Tous droits réservés. Conventions d'Utilisation des Sous-Interrogations • Placez les sous-interrogations entre parenthèses. • Placez les sous-interrogations à droite de l'opérateur de comparaison. • N'ajoutez jamais de clause ORDER BY à une sous-interrogation. • Utilisez les opérateurs mono-ligne avec les sous-interrogations mono-ligne. • Utilisez les opérateurs multi-ligne avec les sous-interrogations multi-ligne.
  8. 8. 7-8 Copyright © Oracle Corporation, 1997. Tous droits réservés. Types de Sous-Interrogations • Sous-interrogation mono-ligne Requête principale sous-interrogation ramèneramène CLERKCLERK • Sous-interrogation multi-ligne CLERKCLERK MANAGERMANAGER Requête principale ramèneramène • Sous-interrogation multi-colonne CLERK 7900CLERK 7900 MANAGER 7698MANAGER 7698 Requête principale ramèneramène sous-interrogation sous-interrogation
  9. 9. 7-9 Copyright © Oracle Corporation, 1997. Tous droits réservés. Sous-Interrogations Mono-ligne • Ne ramènent qu'une seule ligne • Utilisent des opérateurs de comparaison mono-ligne Opérateur = > >= < <= <> Signification Egal à Supérieur à Supérieur ou égal à Inférieur à Inférieur ou égal à Différent de
  10. 10. 7-10 Copyright © Oracle Corporation, 1997. Tous droits réservés. Sous-Interrogations Mono-ligne Afficher les employés occupant le même poste que l’employé No. 7369 ? SELECT ename, job FROM emp WHERE job = ( SELECT job FROM emp WHERE empno=7369 );
  11. 11. 7-11 Copyright © Oracle Corporation, 1997. Tous droits réservés. Exécution de Sous-Interrogations Mono-ligne CLERK 1100 ENAME JOB ---------- --------- MILLER CLERK ENAME JOB ---------- --------- MILLER CLERK SQL> SELECT ename, job 2 FROM emp 3 WHERE job = 4 (SELECT job 5 FROM emp 6 WHERE empno = 7369) 7 AND sal > 8 (SELECT sal 9 FROM emp 10 WHERE empno = 7876);
  12. 12. 7-12 Copyright © Oracle Corporation, 1997. Tous droits réservés. Utilisation de Fonctions de Groupe dans une Sous- Interrogation 800 ENAME JOB SAL ---------- --------- --------- SMITH CLERK 800 ENAME JOB SAL ---------- --------- --------- SMITH CLERK 800 SQL> SELECT ename, job, sal 2 FROM emp 3 WHERE sal = 4 (SELECT MIN(sal) 5 FROM emp); www.TelechargerCours.com
  13. 13. 7-13 Copyright © Oracle Corporation, 1997. Tous droits réservés. Clause HAVING avec Sous- Interrogations • Oracle Server exécute les sous- interrogations en premier. • Oracle Server ramène les résultats dans la clause HAVING de la requête principale. 800 SQL> SELECT deptno, MIN(sal) 2 FROM emp 3 GROUP BY deptno 4 HAVING MIN(sal) > 5 (SELECT MIN(sal) 6 FROM emp 7 WHERE deptno = 20);
  14. 14. 7-14 Copyright © Oracle Corporation, 1997. Tous droits réservés. Exemple • Trouver le poste ayant le salaire moyen le moins élevé . SELECT job, AVG(sal) FROM emp GROUP BY job HAVING AVG(sal) = ( SELECT MIN(AVG(sal)) FROM emp GROUP B job ) www.TelechargerCours.com
  15. 15. 7-15 Copyright © Oracle Corporation, 1997. Tous droits réservés. Qu'est-ce Qui ne Va pas dans cet Ordre ? ERROR: ORA-01427: single-row sub-query returns more than one row no rows selected ERROR: ORA-01427: single-row sub-query returns more than one row no rows selected SQL> SELECT empno, ename 2 FROM emp 3 WHERE sal = 4 (SELECT MIN(sal) 5 FROM emp 6 GROUP BY deptno); O pérateur m ono-ligne avec sous-interrogation m ulti-ligne O pérateur m ono-ligne avec sous-interrogation m ulti-ligne www.TelechargerCours.com
  16. 16. 7-16 Copyright © Oracle Corporation, 1997. Tous droits réservés. Cet Ordre Va-t-il Fonctionner ? no rows selectedno rows selected La sous-interrogation ne ram ène aucune valeur La sous-interrogation ne ram ène aucune valeur SQL> SELECT ename, job 2 FROM emp 3 WHERE job = 4 (SELECT job 5 FROM emp 6 WHERE ename='SMYTHE'); www.TelechargerCours.com
  17. 17. 7-17 Copyright © Oracle Corporation, 1997. Tous droits réservés. Sous-Interrogation Multi-ligne • Ramène plusieurs lignes • Utilise des opérateurs de comparaison multi-ligne Opérateur IN ANY ALL Signification Egal à un élément quelconque de la liste Compare la valeur à chaque valeur ramenée par la sous-interrogation Compare la valeur à toutes les valeurs ramenées par la sous-interrogation www.TelechargerCours.com
  18. 18. 7-18 Copyright © Oracle Corporation, 1997. Tous droits réservés. Exemple • Trouver les employés qui gagnent l’équivalent d’un salaire minimum de département . SELECT ename, sal, deptno FROM emp WHERE sal ( SELECT MIN(sal) FROM emp GROUP B deptno ) IN www.TelechargerCours.com
  19. 19. 7-19 Copyright © Oracle Corporation, 1997. Tous droits réservés. Utilisation de l'Opérateur ANY dans les Sous-Interrogations Multi- ligne 950 800 1100 1300 EMPNO ENAME JOB --------- ---------- --------- 7654 MARTIN SALESMAN 7521 WARD SALESMAN EMPNO ENAME JOB --------- ---------- --------- 7654 MARTIN SALESMAN 7521 WARD SALESMAN SQL> SELECT empno, ename, job 2 FROM emp 3 WHERE sal < ANY 4 (SELECT sal 5 FROM emp 6 WHERE job = 'CLERK') 7 AND job <> 'CLERK'; www.TelechargerCours.com
  20. 20. 7-20 Copyright © Oracle Corporation, 1997. Tous droits réservés. Utilisation de l'Opérateur ALL dans les Sous-Interrogations Multi-ligne 2916.6667 2175 1566.6667 EMPNO ENAME JOB --------- ---------- --------- 7839 KING PRESIDENT 7566 JONES MANAGER 7902 FORD ANALYST 7788 SCOTT ANALYST EMPNO ENAME JOB --------- ---------- --------- 7839 KING PRESIDENT 7566 JONES MANAGER 7902 FORD ANALYST 7788 SCOTT ANALYST SQL> SELECT empno, ename, job 2 FROM emp 3 WHERE sal > ALL 4 (SELECT avg(sal) 5 FROM emp 6 GROUP BY deptno)
  21. 21. 7-21 Copyright © Oracle Corporation, 1997. Tous droits réservés. Résumé Les sous-interrogations sont utilesLes sous-interrogations sont utiles lorsqu'une requête fait appel à des valeurslorsqu'une requête fait appel à des valeurs inconnues.inconnues. SELECT select_list FROM table WHERE expr operator (SELECT select_list FROM table); www.TelechargerCours.com

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