Subqueries That Return Multiple Results : Subquery Basics « Subquery « Oracle PL / SQL






  1. Oracle PL / SQL
  2. Subquery
  3. Subquery Basics

Subqueries That Return Multiple Results

    
SQL>
SQL> CREATE TABLE Course (
  2     CourseID INT NOT NULL PRIMARY KEY,
  3     Name     VARCHAR(50),
  4     Credits  INT);

SQL>
SQL>
SQL> CREATE TABLE Exam (
  2     ExamID      INT NOT NULL PRIMARY KEY,
  3     CourseID    INT NOT NULL,
  4     InstructorID INT NOT NULL,
  5     SustainedOn DATE,
  6     Comments    VARCHAR(255));

SQL>
SQL> SELECT Name FROM Course
  2  WHERE CourseID IN(
  3      SELECT CourseID from EXAM
  4      WHERE SustainedOn='26-MAR-03'
  5  );

no rows selected

SQL>
SQL> drop table course;

Table dropped.

SQL> drop table exam;

Table dropped.








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