Using count, PL-SQL Programming

Assignment Help:

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 condition is true:

IF projects.COUNT = 15 THEN...

The COUNT is very useful as the present size of a collection is not always known. For e.g. if you fetch a column of the Oracle data into a nested table, then how many elements does the table contain? The COUNT provides you the answer.

You can also use the COUNT where an integer expression is allowed. In the next e.g. you use COUNT to specify the upper bound of a loop range:

FOR i IN 1..courses.COUNT LOOP ...

For the varrays, the COUNT is always equals to LAST. For nested tables, COUNT generally equals to LAST. But, if you delete elements from the middle of a nested table, then the COUNT becomes smaller than LAST.


Related Discussions:- Using count

Cursor variables, What Are Cursor Variables  ? The Cursor variables ar...

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, decl

Example of when or then constraints - sql, Example of WHEN or THEN Constrai...

Example of WHEN or THEN Constraints A concrete example showing how SQL supports WHEN/THEN constraints CREATE TABLE SAL_HISTORY (EmpNo CHAR (6), Salary INTEGER NOT NULL,

Group and having query, Using a join on 2 tables, select all columns and 10...

Using a join on 2 tables, select all columns and 10 rows from the 2 tables without the use of a Cartesian product. Query: SELECT * FROM EMPLOYEE1 E JOIN STAFF S ON E.EMP_

Opening a cursor, Opening a Cursor Opening the cursor executes the que...

Opening a Cursor Opening the cursor executes the query & identifies the result set that consists of all rows that meet the query search criteria. For the cursors declared usin

Delete command - sql, DELETE Command - SQL Loosely speaking, DELETE re...

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 Suppose the university decides that course C3 is to be withdrawn.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 except operator - sql, Example of EXCEPT Operator - SQL Ex...

Example of EXCEPT Operator - SQL Example, like its counterpart in the theory book, illustrates the convenience of allowing any table expression to be the source for an INSERT

Implement a new discount for return shoppers, Brewbean's is implementing a ...

Brewbean's is implementing a new discount for return shoppers - every fifth completed order receives a 10% discount. The count of orders for a shopper is placed in a packaged varia

Updating variables, Updating Variables For assignment, SQL uses the ke...

Updating Variables For assignment, SQL uses the key word SET, as in SET X = X + 1 (read as "set X equal to X+1") rather than X: = X + 1 as found in many computer languages.

Level - sql pseudocolumns, LEVEL You use the LEVEL with the SELECT CON...

LEVEL You use the LEVEL with the SELECT CONNECT BY statement to categorize rows from a database table into a tree structure. The LEVEL returns the level number of a node in a

Using invoker rights in pl sql, Using Invoker Rights: By default, the ...

Using Invoker Rights: By default, the stored procedure executes with the privileges of its definer, not its invoker. These procedures are bound to the schema in which they inh

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