Using exists - collection methods, PL-SQL Programming

Assignment Help:

Using EXISTS

The EXISTS(n) returns TRUE if the nth element in a collection exist. Or else, EXISTS(n) returns FALSE. Primarily, you use EXISTS with DELETE to maintain the sparse nested tables. You can also use EXISTS to avoid raising an exception whenever you reference a nonexistent element. In the example below, the PL/SQL executes the assignment statement only if the element i exists:

IF courses.EXISTS(i) THEN courses(i) := new_course; END IF;

When passed an out-of-range subscript, the EXISTS returns FALSE instead of raising SUBSCRIPT_OUTSIDE_LIMIT.


Related Discussions:- Using exists - collection methods

Long and long raw in pl/sql, LONG and LONG RAW You use the LONG datatyp...

LONG and LONG RAW You use the LONG datatype to store the variable-length character strings. The LONG datatype is such as the VARCHAR2 datatype, except that the maximum length o

Using first and last - collection method, Using FIRST and LAST FIRST a...

Using FIRST and LAST FIRST and LAST return the first and last (minimum and maximum) index numbers in a collection. When the collection is empty, the FIRST and LAST return NULL

Named notation, Named Notation The second procedure call uses the name...

Named Notation The second procedure call uses the named notation. An arrow (=>) serve as the relationship operator that associates the formal parameter to the left of the arro

Packaging cursors, Packaging Cursors   You can split a cursor specific...

Packaging Cursors   You can split a cursor specification from its body for placement in a package. In that way, you can change the cursor body without changing the cursor spec

Collection methods in pl sql, Collection Methods:   The collection me...

Collection Methods:   The collection method is a built-in function or procedure which operates on the collections and is called using the dot notation. The methods like the C

Using %rowtype-declarations in sql, Using %ROWTYPE The %ROWTYPE attribut...

Using %ROWTYPE The %ROWTYPE attribute gives a record type which represents a row in a table (or view). The record can store the whole row of data selected from the table or fetc

Negation - sql, Negation (NOT, ¬) - SQL There are three rows instead o...

Negation (NOT, ¬) - SQL There are three rows instead of just two. As you can see, ¬ p is defined as in two-valued logic (2VL) when p is either true or false, but ¬ (unknown) i

Sql operators, SQL Operators The PL/SQL uses all the SQL set, compariso...

SQL Operators The PL/SQL uses all the SQL set, comparison, and row operators in the SQL statements. This part briefly describes some of these operators.  1. Comparison Opera

Sql is a database language, SQL Is a Database Language: The commands g...

SQL Is a Database Language: The commands given to a DBMS by an application are written in the database language of the DBMS. The term data sublanguage is sometimes used instea

Merge and truncate in sql, MERGE and TRUNCATE in SQL SQL has two more ...

MERGE and TRUNCATE in SQL SQL has two more table update operators, MERGE and TRUNCATE. MERGE, like INSERT, takes a source table s and uses it to update a target table t. Brief

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd