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!
What Are Cursor Variables ?
The Cursor variables are like C or Pascal pointers that hold the memory location (address) of some item rather of the item itself. Therefore, declaring a cursor variable creates a pointer, not an item. In the PL/SQL, the pointer has a datatype REF X, where REF is short form for the REFERENCE and X stands for the class of objects. Therefore, a cursor variable has the datatype REF CURSOR.
To execute a multi-row query, the Oracle opens an unnamed work region which stores processing the information. To access the information, you can use an explicit cursor that names the work area. Or, you can use a cursor variable that points to the work region. While the cursor always refers to the similar query work region, a cursor variable can refer to various work regions. Therefore, the cursors and cursor variables are not interoperable.
Using %TYPE The %TYPE attribute gives the datatype of a variable or the database column. In the example below, the %TYPE gives the datatype of a variable: credit REAL(7,2); debi
Table Represents an Extension - SQL It describes how each tuple in a relation represents a true instantiation of some predicate and each true instantiation is represented by s
Predefined Exceptions The internal exception is raised implicitly whenever your PL/SQL program exceeds a system-dependent limit or violates an Oracle rule. Each & every Oracle
INSERT Statement The INSERT statement adds fresh rows of data to the specified database table or view. Syntax:
Using Pragma RESTRICT_REFERENCES: The function called from the SQL statements should obey certain rules meant to control the side effects. To check for violation of the rules,
Ending Transactions A good quality programming practice is to commit or roll back every transaction explicitly. Whether you rollback or issue the commit in your PL/SQL program
Inserting Objects: You can use the INSERT statement to add objects to an object table. In the illustration below, you insert a Person object into the object table persons:
Question: (a) The objective of query optimization is to choose the most efficient strategy for implementing a given relational query, thereby improving the system performance. On
Iterative Control: LOOP Statements The LOOP statement executes a series of statements multiple times. There are 3 forms of LOOP statements: LOOP, WHILE-LOOP, & FOR-LOOP. LOOP
Example of NOT EXISTS Operator - SQL Example is a translation into SQL of the corresponding example, which is included there merely to show that for any scalar comparison the
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