Answer / sowmya

Hi
cursors allow row -by-row processing of the resultsets
Types of cursors are: static,dynamic,
forward-only,keyset-driven,

disadvantages of cursors are : each time you fetch a row
from the cursor,it results in a network roundtrip,where are
as normal select query makes only one round trip
cursors are costly as they need temparory storage.

Answer / kamal

Cursor is a named private SQL area from where information
can be accessed. Cursors are required to process rows
individually for queries returning multiple rows.


Within the library cache, parsed SQL is stored as cursors.
The cursors are indexed by handlers referencing memory
locations within which parsed statements and information
relating to processing are stored. A context area is a
shared area of memory that stores the environment and
session variables for an instruction. Buffer caches store
active data and use a cache replacement scheme storing the
most recently used data.

Answer / anil kumar jaiswal

cursor :

Oracle create a memory area called context area to execute sql statements. that context area keep all information about the statement processed.
cursor is just a pointer to that context area and you can also say a cursor is pointing to result set of a query.
Types cursor :
1.Implicit cursor : implicit cursor automatically created by oracle when ever there is dml operation performed inside pl/sql block.(dml operation means insert,update,delete).
2. Explicit Cursor : its a user defined cursor, user need to define it explicitly.
cursor declared in declaration section called explicit cursor.

Cursor Attributes : there is 4 types of cursor attributes used.
1.%notfound.
2.%found.
3.%isopen
4.%rowcount.
for more queries contact me on aniljaiswal143@gmail.com.

Answer / ragaventhar

Cursor is used to fetch the data from a main table to temporary variable at run time and it is affected row by row .Mainly used to stored a data temporary and give the result set at the time of run time

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