SlideServe
Télécharger Obtenir Pro
Menu
Accueil Pro
Préférences
ApparenceLight Aide et commentaires
© SlideServe · v2026

Structured Query Language

oliver avatar
oliver
11 diapositives · 242 Views · Sep 29, 2014

This guide provides a comprehensive overview of SQL querying techniques, focusing on both single and multiple table queries. Learn how to effectively use the SELECT statement, apply filtering with WHERE clauses, aggregate data with built-in functions, and manipulate data through INSERT, UPDATE, and DELETE operations. Gain insights into subqueries, JOINs, and the use of EXISTS and NOT EXISTS conditions. Enhance your SQL skills and become proficient in database querying and data management with practical examples.

#structured query language #structured query language ppt #powerpoint #presentation
Structured Query Language - slide 1
01 / 11Structured Query Language
1 / 17

Télécharger la présentation

Structured Query Language
Une image / un lien ci-dessous est fourni (tel quel) pour télécharger la présentation

Politique de téléchargement : le contenu du site vous est fourni TEL QUEL pour votre information et votre usage personnel ; il ne peut être vendu, concédé sous licence ni partagé sur d’autres sites sans l’accord de son auteur.Le contenu vous est fourni TEL QUEL, pour votre information et votre usage personnel uniquement. Téléchargez la présentation en cliquant sur ce lien. Lors du téléchargement, si vous ne parvenez pas à télécharger une présentation, l’éditeur a peut-être supprimé le fichier de son serveur.Pendant le téléchargement, si vous ne parvenez pas à obtenir une présentation, le fichier a peut-être été supprimé par l’éditeur.

F I N

Plus de contenu associé

Transcription de la présentation

  1. Structured Query Language • Querying a Single Table • Querying Multiple Tables • EXISTS and NOT EXISTS • Changing Data

  2. Querying a Single Table • Projections Using SQL • SELECT Major FROM STUDENT and SELECT DISTINCT Major FROM STUDENT

  3. Querying a Single Table (Cont.) • Selections Using SQL • SELECT Name, Age FROM STUDENT WHERE Major=‘MATH’ AND Age>21 and SELECT Name FROM STUDENT WHERE Major IN [‘MATH’,’HISTORY’]

  4. Querying a Single Table (Cont.) • Sorting • SELECT Name, Major, Age FROM STUDENT WHERE GradeLevel IN [‘FR’,’SO’,’SN’] ORDER BY Major ASC, Age DESC

  5. Querying a Single Table (Cont.) • SQL Built-In Functions • COUNT, SUM, AVG, MAX, MIN • e.g. SELECT COUNT(DISTINCT Major) FROM STUDENT and SELECT Major, COUNT(*) FROM STUDENT WHERE Major IN [‘MATH’,’HISTORY’] GROUP BY Major HAVING COUNT(*)>2

  6. Querying Multiple Tables • Using Subqueries • What are the names of the students enrolled in the class BD445? SELECT Name FROM STUDENT WHERE SID IN (SELECT StudentNumber FROM ENROLMENT WHERE ClassName=‘BD445’)

  7. Querying Multiple Tables (Cont.) • What are the names of the students enrolled in classes on Monday, Wednesday, and Friday at 3 o’clock (MWF3)? SELECT STUDENT.Name FROM STUDENT WHERE STUDENT.SID IN (SELECT ENROLLMENT.StudentNumber FROM ENROLLMENT WHERE ENROLLMENT.ClassName IN

  8. Querying Multiple Tables (Cont.) (SELECT CLASS.Name FROM CLASS WHERE CLASS.Time=‘MWF3’))

  9. Querying Multiple Tables (Cont.) • Joining with SQL • List the student number and class name of all students named RYE who were first to enroll in a class. SELECT STUDENT.SID, ENROLMENT.ClassName FROM STUDENT, ENROLLMENT WHERE STUDENT.SID=ENROLLMENT.StudentNumber AND ENROLLMENT.PositionNumber=1 AND STUDENT.Name= ‘RYE’

  10. Querying Multiple Tables (Cont.) • EXISTS and NOT EXISTS • List the student numbers of students enrolled in more than one class. SELECT DISTINCT StudentNumber FROM ENROLLMENTA WHERE EXISTS (SELECT * FROM ENROLLMENTB WHERE A.StudentNumber=B.StudentNumber AND A.ClassName NOT = B.ClassName)

  11. Querying Multiple Tables (Cont.) • CHANGING DATA • Inserting Data INSERT INTO ENROLLMENT VALUES(400,’BD445’,44) • Deleting Data DELETE STUDENT WHERE STUDENT.Major=‘Accounting’ • Modifying Data UPDATE ENROLLMENT SET PositionNumber=44 WHERE SID=400