what is a cursor
Answers were Sorted based on User's Feedback
Answer / ganesh
cursor is a small work area like memory which are given by
oracle to execute sql statement, after execution this space
are made free for another sql staments to execute.
when we use the cursor with cursor name for a tble,then
that cursor will bring those from database one by one and
will keep in cursor memory for execution.
Is This Answer Correct ? | 10 Yes | 2 No |
Answer / s.syam sundar
oracle uses a private area to process and store data.this
private area is called as cursor
we have two types of cursors
they are implict and explict
implict cursor:- it is a cursor which controlled by oracle
itself
Ex: select statmets,insert,update and delete statmets
explict cursors:- it is a cursor which controlled by
programmer
controlling means
open cursor
fetch into
close cursor
Ex: create cursor c1(cursor name) as select * from emp
where deptno =10;( this is in declarative section)
in excutable section:
open cursor c1;
fetch cursor c1 into some veriable or table name;
......
.....
close c1
we can use parameters in cursors
and we can not assiagn cursor name to a variable
and we need not use cursor statemets in for update cursor
because it will take care of
regards
S.syam sundar
Is This Answer Correct ? | 4 Yes | 1 No |
Answer / t.r.sekhar
cursor is a temporary buffer used to hold the transactional
data for the manipulation purpose.
data will not permanently stored in database.
it is not reusable.
syntax:
cursor <cursor name> is <select stmt);
we have two types of cursors are there.
1.implicit cursors-automatically created whenever dml
statements are executed.
2.explicit cursors-created by user
Is This Answer Correct ? | 3 Yes | 0 No |
Answer / suriya
Cursor is a mechanism by which we can name a 'select
stataments' and manipulate the information within that.
They are very useful, when we need to run a particular SQL
repeatedly.
Cursors are of 2 types, Implicit and Explicit.
Implicit Cursors: All the select statements we run are
implicitly stored in a cursor, by default. They are defined
by oracle.
Explicit Cursors: This is like user defined cursor. The
user can declare and use a cursor of his own requirement.
The operations performed with a cursor are declaring,
opening,fetching and closing.
Note:Leaving a cursor unclosed, will cause error.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / kishor
Cursor is a pointer to the context area where data is
stored and fetched row by row.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / gourvendra singh
A Cursor is a handle (a name or pointer) for the memory
associated with a specific statement. It is of two type
Implicit and explicit, we usually create explicit cursor
for our sql statements, we can also save them by providing
them a name.
Is This Answer Correct ? | 2 Yes | 2 No |
cursor acts as datatype for holding composite
variable.composite variable hold more than one value at a
time.
when ever u declare a cursor it tells to sqlserver that
memory is create for that cursor
whenever u open the cursor it executes select statement in
declare section and reserves memory stored the result of
execution in this memory.and reserves pointer to the before
first
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / s.syam sundar
oracle uses a private area to process and store data.this
private area is called as cursor
we have two types of cursors
they are implict and explict
implict cursor:- it is a cursor which controlled by oracle
itself
Ex: select statmets,insert,update and delete statmets
explict cursors:- it is a cursor which controlled by
programmer
controlling means
open cursor
fetch into
close cursor
Ex: cursor c1(cursor name) is select * from emp
where deptno =10;( this is in declarative section)
in excutable section:
open cursor c1;
fetch cursor c1 into some veriable or table name;
......
.....
close c1
we can use parameters in cursors
and we can not assiagn cursor name to a variable
and we need not use cursor statemets in for update cursor
because it will take care of
regards
S.syam sundar
Is This Answer Correct ? | 0 Yes | 1 No |
how do you restrict number of rows for a particular value in a column.For example:there is a table called fruits,having apples,bananas ,papayas.I dont want to have more than 100 apples in that table ,so how can u restrict number of rows for apple to hundred?
need to split a string into seperate values. eg. col1 col2 ---------- 100 - 'a,b,c' 200 - 'a,x,b,d,e' 300 - 'c' result: value count ------------- a - 2 b - 1 c - 2 etc.
What are functions in sql?
how can create data base link for tow servers (scott schema) give examples plz
What do you understand by pl/sql records?
What is difference between mysql and postgresql?
Does user triggers have entry for trigger with compilation errors?
What is a data manipulation language?
HOW TO TUNE ORACLE SQL QUERIES GIVE ME STEP BY SREP
What is sqlservr exe?
What is the difference between instead of trigger and after trigger?
How to call the function and Procedure in trigger?