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!
Understanding Nested TablesWithin the database, the nested tables can be considered as one-column database tables. The Oracle stores the rows of a nested table in no specific order. But, when you retrieve the nested table into the PL/SQL variable, the rows are given consecutive subscripts starting at 1. That provides you array-like access to the individual rows.Within PL/SQL, the nested tables are like one-dimensional arrays. Though, nested tables differ from arrays in two significant ways. Firstly, the arrays have a fixed upper bound, but nested tables are unbounded .Therefore, the size of a nested table can increase dynamically.
Figure: Array versus Nested TableSecondly, the arrays should be dense (having consecutive subscripts). Therefore, you cannot delete individual elements from an array. Initially, the nested tables are dense, but they can be sparse (having nonconsecutive subscripts). And hence, you can delete elements from a nested table using the built-in procedure DELETE. That might leave gaps in the index, but the built-in function NEXT iterate over any series of subscripts.
Character Types The Character types allow you to store alphanumeric data, represent words and text, and manipulate the character strings. CHAR You use the CHAR dataty
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 Suppose the university decides that course C3 is to be withdrawn.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
Example of Null operator - NiNo Rule If we wanted to make HIGHER_OF adhere to "NULL in, NULL out"-let's call it the NiNo rule-we would have to write something like what is sho
Effects of NULL Operator As a general rule-but not a universal one-if NULL is an argument to an invocation of a system-defined read-only operator, then NULL is the result of t
Interesting properties of CROSS JOIN - SQL Compare these with the "interesting properties of JOIN", CROSS JOIN is associative but not commutative. Unlike JOIN and NATURAL JOI
Effects of NULL for union - SQL The treatment of NULL in invocations of EXCEPT is as for UNION. This is different from its treatment in those of NOT IN and quantified compari
Restriction and AND - SQL Restriction is available via the WHERE operator, and so it is in SQL. However, by Example showing how a certain simple restriction can be expressed u
Parameter & Keyword Description: function_name: The user-defined function is identifying by that keyword. parameter_name: This identifies the formal parameter that
Indeterminacy in SQL Some SQL expressions are actually not function invocations at all in the mathematical sense, being indeterminate-invocations operating on identical input
Cursor Attributes The Cursors and cursor variables have 4 attributes which give you helpful information about the execution of a data manipulation statement. Syntax:
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