Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Example of Cast Operator
So long as CAST is used as shown, we could obtain the total marks for each exam in similar fashion, using SUM (Mark) AS TotalMarks. However, this gives NULL, instead of zero, for the courses whose exams nobody sat. That problem can be addressed by using COALESCE, as shown in Example.
Example: Give the total of marks for each exam
WITH C_ER AS (
SELECT CourseId,
CAST (
TABLE (SELECT DISTINCT StudentId, Mark
FROM EXAM_MARK AS EM
WHERE EM.CourseId = C.CourseId )
AS ROW ( StudentId SID, Mark INTEGER) MULTISET)
AS ExamResult
FROM COURSE AS C)
SELECT CourseId, (SELECT SUM (Mark)
FROM TABLE(ER (ExamResult)) AS t) AS n
FROM C_ER
Explanation
CURRVAL and NEXTVAL The series is a schema object which generates the sequential numbers. Whenever you form a sequence, you can specify its primary value and an increment. T
(a) What are decision support systems, and what role do they play in the business environment? (b) Data warehousing is defined as "a subject-oriented, integrated, non-volatile c
DELETE Command - SQL Loosely speaking, DELETE removes some existing rows from its target table. Suppose the university decides that course C3 is to be withdrawn. Example shows
Attributes: Just similar to variable, an attribute is declared with a name and datatype. The name should be exclusive within the object type. The datatype can be any Oracle ty
Manipulating Objects: You can use an object type in the CREATE TABLE statement to indicate the datatype of a column. When the table is created once, you can use the SQL statem
Deleting Objects You can use the DELETE statement to eradicate objects from an object table. To eradicate objects selectively, you use the WHERE clause, as shown below: BEG
BETWEEN Operator The operator BETWEEN, tests whether the value lies in a specified series. That means "greater than or equivalent to low value and less than or equivalent to hig
Effect of Anonymous Columns Now, recall that a VALUES expression denotes a table with undefined column names. If an initial value is to be specified when a base table is creat
Inner Join We have learned how to retrieve data from one table by using SELECT statement. But, as we have learned, normalized relational databases mean the data is spread betw
Keyword and Parameter Description select_statement: This is a query which returns a result set of the rows. Its syntax is such that of select_ into_statement without the IN
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd