A normal cursor is a simple cursor which act as a static one where as ref cursor is a dynamic cursor which acts dynamically at run time. In plsql what is a difference between a cursor and a. Unlike an explicit cursor, which always refers to the same query work area, a cursor variable can refer to different work areas. This example demonstrates how to define and open a ref cursor variable, and then pass it as a procedure parameter. A cursor variable has datatype ref cursor, and you might see them referred to informally as ref cursors. Typically the ref cursor definition and the open for. Find answers to convert is ref cursor from oracle to sql 2008 from the. Ref cursor s are represented through the oraclerefcursor odp. There was this comparison between explicit and implicit cursors. A ref cursor is a datatype that holds a cursor value in the same way that a varchar2 variable will hold a string value. The comparison value for col1 is inserted via a using parameter, so it needs no quoting.
This is normally used to open a query on the database server, then leave it up to the client to fetch the. Dec 20, 2016 i hope before knowing about ref cursors you would have a fair idea of what cursors in general are. This example executes a plsql stored procedure that returns two ref cursor parameters, and reads the values using an oracledatareader. The basic difference between normal cursor and ref cursor is as follows. A cursor is once define its contents are fixed and cant be changed. There he asked one question as what is the difference between cursor and ref cursor, and when would you appropriately use each of these. There actually are simple steps to dramatically reduce online tracking. For how many years have you been working with physical servers that are starving your database of the memory necessary to deploy important new performance features such as the result cache, memoptimize pool, inmemory aggregation, inmemory column store, and full database caching. To use the cursor on your web or a myspace profile, add the following code to your page.
I am sure, this question has been asked in many interviews to many of us and it also has its own technical weightage. A normal cursor behaves likes a constant whereas a ref cursor behaves like a variable. A ref cursor is a variable, so you can pass it between proceduresfunctions. Once a cursor variable is opened with a query statement, it will have the same attributes as a normal cursor and it can be used in the same way a normal cursor too. Visit the open icon library and download thousands of icons from various authors.
Free normal select cursor icon normal select cursor. Normal cursors fall under the category of static cursors while ref cursors are dynamic. What is difference between weak reference type and strong. Normal cursor is a static cursor in which the query is assigned at design time and cant be changed at run time. A ref cursor can be passed from one procedure to another. In essence, a ref cursor is a pointer or a handle to a result set on the database. What is the difference between a reference cursor and. Home about download documentation community developers. Difference between a hot backup and a cold backup in oracle. What is the difference between sql, plsql and tsql.
Please tell me diff between ref cursor and cursor with examples thanks hi normal cursor doesnt return the any values ref cursor does return the values. Convert is ref cursor from oracle to sql 2008 solutions. Click on advance under the add custom css textarea box paste the following at the very bottom and save. A cold backup is done when there is no user activity going on with the system. Registered users may also upload and publish their icons. Jun 21, 2010 the smiley normal select tumblr cursor will work on your page if you follow these instructions. I have a ref cursor defined as an out parameter and i am trying to get a receiving plsql to accept the ref cursor. Feb 19, 20 delta between two data cursor points in plot. As other answers pointed out they are memory structures used to temporarily store and iterate through a query result set in plsql. Available in png, ico or icns icons for mac for free use.
A ref cursor is a variable, defined as a cursor type. Difference between cursor and ref cursor in oracle. In dynamic cursors the contents of cursor can be changed dynamically depending upon the situation. This means that normal cursors can only be used again not defined. You cannot use a cursor variable where a cursor is expected, or vice versa. Rwdesigner flickr group post your photos to rwdesigner group on flickr. A ref cursor can be opened on the server and passed to the client as a unit rather than fetching one row at a time. There are some important differences between regular cursors and ref cursors which are following. Ref cursor can be passed from one procedure to other procedure but cursor cant be passed from one procedure to other. In addition, a select or function cursor can specify readonly or update mode. Generally ref cursor used for passing cursor parameter and. In plsql what is a difference between a cursor and a reference cursor. You cannot define the same cursor more than stead you can only use it. Normal cursor are static cursors and also we cant able to.
A more interesting usage is to return a reference to a cursor that a function. However, plpgsql users do not normally need to worry about that, since for. Retrieving data from multiple ref cursors using an oracledatareader. Also called as offline backup, is taken when the database is not running and no users are logged in. Cursors can also have sequential, scroll, and hold characteristics but an insert cursor cannot be a scroll cursor. What is the difference between a normal cursor and a ref. Returning a ref cursor from a procedure plsql this example demonstrates how to define and open a ref cursor variable, and then pass it as a procedure parameter. Difference between cursor and ref cursor oracle database. The cursor variable is specified as an in out parameter so that the result set is made available to the caller of the procedure. Ref cursors are typically used to change the where clause of a query, based on user input. He stated that explicit cursor is faster than implicit because implicit cursors have to make an extra fetch to test for row existence. The return type of a function may also be a ref cursor type. Can i see some examples of working ref cursor examples, especially passing a ref cursor between two programs. This video explains about ref cursor in oracle plsql, what are ref cursors, how are ref cursor different from simple cursors, what are the advantages of using a ref cursor etc.
Oracle ref cursor tips oracle database tips by donald burlesonmay 5, 2015 the oracle ref cursor is a pointer data types that allows you to quickly reference any cursor result usually an internal plsql table array with data values kept in superfast ram. These characteristics determine the structure of the cursor. What is the difference between a normal cursor and a ref cursor. Ref cursor is typically used to return record set or a cursor from stored procedure. Sections that follow describe each of these cursor types. A ref cursor is a plsql data type whose value is the memory address of a query work area on the database. Difference between cursor and ref cursor in this post i am trying to detail out the differences between cursor and ref cursors. This example executes a plsql stored procedure that returns a ref cursor parameter, and reads the value as an oracledatareader. A cursor cant be passed as parameter from subroutine to subroutine. For information about strong and weak ref cursor types, see creating cursor variables. Delta between two data cursor points in plot matlab answers. Hi, while giving with hold for that mean the lock is been applied on the table and no it wont allow any other program to use the table, when it come to performance if you use with hold even after the commit the cursor wont release the value while if you are not mentioning the with hold option then just after the commit the value will be released, this save the resource use and considered to be.
There are lots of differences in ref cursor oracle and. Learn how to create animated cursors in a video tutorial. Ask tom difference between cursors for loop and normal. Aug 06, 2015 how to test a oracle stored procedure with ref cursor from sqlplus or sql developer. Plsql composite data type collections associative array, varray and nested tables kafka java producer and consumer. Normal cursor are static cursors and also we cant able to pass like paramater.
Generally ref cursor used for passing cursor parameter and also dynamically building the query. Comparison operators cannot be used to test cursor variables for equality. Ref cursors may be dynamically opened or opened based on logic. Smiley normal select cursor free cursors 4u, tumblr cursor. Hi tom, feels good that i got a chance to ask you a question. In plsql what is a difference between a cursor and a reference. Diff between cursor and reference cursor answer kavitharaveenthiran. Free normal select cursor icon normal select cursor icons.
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