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!
Aggregate AssignmentThe %ROWTYPE declaration cannot include an initialization clause. Though, there are two ways to assign values to all fields in a record at once. At First, the PL/SQL allows the aggregate assignment between the whole records if their declarations refer to the similar table or cursor. For illustration, the assignment below is legal:DECLAREdept_rec1 dept%ROWTYPE;dept_rec2 dept%ROWTYPE;CURSOR c1 IS SELECT deptno, dname, loc FROM dept;dept_rec3 c1%ROWTYPE;BEGIN...dept_rec1 := dept_rec2;However, because dept_rec2 is based on a table and dept_rec3 is based on acursor, the following assignment is illegal:dept_rec2 := dept_rec3; -- illegalSecondly, you can assign a list of column values to a record by using the SELECT or FETCH statement, as the illustration below shows. The column names should appear in the order in which they are defined by the CREATE TABLE or CREATE VIEW statement.DECLAREdept_rec dept%ROWTYPE;...BEGINSELECT deptno, dname, loc INTO dept_rec FROM deptWHERE deptno = 30;
Wrapping and unwrapping in SQL Operators WRAP and UNWRAP in connection with attributes whose declared types are tuple types. Example shows how extension and projection can be
Providing Results of Queries Expressing queries in SQL is the (big) subject. Here I present just a simple example to give you the flavour of things to come in those chapters.
FETCH Statement The FETCH statement retrieve rows of data one at a time from the result set of the multi-row query. The data is stored in fields or variables which correspond t
which operation is used if we are interested in only certain columns of a table?
WHEN or THEN Key Constraints Suppose a table has two columns representing a period of time throughout which the information conveyed by the other columns is recorded as having
Parameter and Keyword Description: select_item: This select_item is a value returned by the SELECT statement, and then assigned to the equivalent variable or field in the
Committing and Rolling Back The COMMIT and ROLLBACK end the active autonomous transaction but do not exit the autonomous routine. As the figure shows, if one transaction ends,
Using COUNT The COUNT returns the number of elements that a collection presently contains. For instance, when a varray projects contains 15 elements, then the following IF con
LAWS / RULES - Dollo's Law : Living organisms do exhibit evolutionary irreversibility or evolution is irreversible. Williston's Law
Row Counterparts of Table Operators SQL does not have counterparts tuple rename, tuple projection, tuple extension, tuple join and tuple compose. To obtain the same effects as
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