Getting ref cursors from oracle procedure in data access application blocks rss. The another big advantage here is that the oracle developers can provide. The validation of the rows could be performed by expensive queries. The second cursor should use a value from the first cursor in the where clause. There are two types of cursor variable 1week ref cursor. This will not work because there is no effective parameter provided unless you have already declared a default value for the formal parameter in the cursor definition which is not the. Oracle database plsql users guide and reference stanford. I have to execute an oracle stored procedure from test complete that returns a refcursor, i tried different ways with parameter object and also using the record set my stored procedure exm create or replace procedure testproc retcur out globalpkg. A cursor variable is a variable that references to a cursor. I have a forms 6i that makes a call to the function, with the intent of fetching the data associated with the ref cursor. Bulk implicit cursor aka, select bulk collect into. How can i use a ref cursor returned from an oracle stored. How to use weak ref cursors and bulk collects into a table.
It is an example of a starting point of how you can retrieve data from an oracle database via a stored procedure that returns a cursor. The sample retrieves the ref cursor into a result set object. You can use variables of type urowid to store rowids in a readable format. Using plsql stored procedures and ref cursors oracle docs. For each deleted row an entry in a logfile should be created. How to fetch data from the refcursor oracle community. Background daab is used in a variety of situations such as reading data for display, passing data through application layers, and submitting changed data back to the database system. Using plsql stored procedures and ref cursors oracle. Net, the bottom toolbar always shows the xy coordinates of the cursor.
Creating a plsql stored procedure that uses ref cursors. Meaning that a cursor variable can be opened for any query. A cursor variable can be associated with different queries at runtime. The plsql function must ensure that the ref cursor is opened and associated with a select statement that has a select list that matches the ref cursor type. Plsql ref cursor and oraclerefcursor oracle help center. 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 name ref cursor can be confusing because a ref cursor variable is not a cursor, but a variable that points to a cursor. To create a ref cursor query, you first create a package spec that defines the ref cursor. The cursor variable is specified as an in out parameter so that the result set is made available to the caller of the procedure. The where current of statement allows you to update or delete the record that was last fetched by the cursor. Jun 16, 20 but if you look carefully your code, there is actually no argument provided for this cursor once the cursor has been opened within the second inner for loop. Demos, syntax, and example code of oracle plsql strongly typed and weakly typed ref cursors. Mar 29, 2011 fragile cursor management in oracle database 10g release 1. It has worked consistently until the upgrade to oracle 11g.
Declare type empcurtyp is ref cursor return emp%rowtype. Plsql cursor variables with ref cursor oracle tutorial. Say the business requirement changes so that the data should be displayed in a different order. An implicit cursor is a sql statement that is contained within the executable section of the program and has an into statement as in the case of a select statement. In essence, a ref cursor is a pointer or a handle to a result set on the database. Assuming youre not asking about cursors, and that part is working for you, i would change the select statement to output the data in delimeted format. In 10g the cursor will contain the expected results but in 11g the cursor will be empty. Feb 17, 2010 how to use ref cursor example a ref cursor is basically a data type. Jun 09, 2009 this article explains how to work with oracle stored procedure which returns multiple ref cursors using data access application block daab of enterprise library.
Prior to 11g calling function must return not only ref cursor, but the original query also. The image is upsidedown, so the upperleft of the tool is the lowerleft for the. I need to see a working plsql block that uses where current of and please explain how it works. Here is an example where we are updating records using the where current of statement. One can use a ref cursor as target of an assignment, and it can be passed as parameter to other program units. But the problem i see is not that your ref cursor is too big a ref cursor is not a statement but a result set, but the sql statement in your example will be bigger than the allowable 64k. In addition to providing the performance improvements described in earlier sections, cursor functionality now extends beyond queries, and it is. Dec 20, 2016 i hope before knowing about ref cursors you would have a fair idea of what cursors in general are. Assuming youre not asking about cursors, and that part is working for you, i would change the select.
A ref cursor that specifies a specific return type. Potentially, you need to fetch the ref cursor into transient or persistent storage ill come back to this in a future blog post challenges. As the oracle database has evolved over time, so has the humble cursor. I hope before knowing about ref cursors you would have a fair idea of what cursors in general are. Oracle magazine subscriptions and oracle white papers. The best way to tackle this problem is not to use functions, but procedures and to specify the last parameter as an out cursor. Net microsoft patterns and practices entlib getting ref cursors from oracle procedure in data access application. The advantage that a ref cursor has over a plain cursor is that is can be passed as a variable to a procedure or a function. With an implicit cursor, oracle will handle everything for you, but there is a cost to doing this. Cursor management in oracle database 10g release 1 seems extremely fragile. Returning multiple ref cursors from oracle using daab. How to write data from ref cursor into an csv file kamal kishore aug 24, 2004 11. Ref cursor in oracle forms solutions experts exchange. Cursor can be attached to only one query while ref cursor can be used to associate multiple queries at run time.
Net type for the ref cursor type this section discusses the following aspects of using the ref cursor data type and oraclerefcursor objects obtaining an oraclerefcursor object. Using the cursor for loop in plsql for oracle database 12c. This allows you to retrieve multiple rows from the database if. How to write data from ref cursor into an csv file. The steps in this section will help you create package specs that define ref cursors. Each ref cursor query is associated with a plsql function that returns a strongly typed ref cursor. Cursor variables based on strong and weak ref cursor types create or. This allows you to retrieve multiple rows from the database if your result set should do this. You need to be able to describe any plsql ref cursor in a uniform way across all editions of oracle database from 10g release 1 and newer. Nov 28, 20 reference cursor ref cursor basically, ref cursor is a data type, just like varchar is a variable and holds the value of a string, similarly the ref cursor type holds a cursor. This function retuns a cell array with the desired data associated with the oracle cursor returned by the stored procedure, but does not have all the options of runstoredprocedure. 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. The cursor for loop is the result of combining the select cursor with a for loop we go into additional detail about this loop in the next section.
Ask tom fetch ref cursor to another ref cursor oracle. When using the data provider to work with oracle ref cursors, you should consider the following behaviors. This article explains how to work with oracle stored procedure which returns multiple ref cursors using data access application block daab of enterprise library. The primary advantage of using cursor variables is their capability to pass result sets between sub programs like stored procedures, functions, packages etc. A ref cursor is a datatype that holds a cursor value in the same way that a varchar2 variable will hold a string value 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. 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. You get a better sense of the power of the cursor in oracle by combining it with a loop. Now we will examine how ref cursor examples are tested. The ref cursor is a data type in the oracle plsql language. Returning columns with datatype and length need to be known at compile time. The function creates dynamic sql and initiates the open of the cursor. Sep 27, 2005 oracle ace director and oracle developer champion.
As other answers pointed out they are memory structures used to temporarily store and iterate through a query result set in plsql. Below is an example of how to declare a cursor within a cursor. Using ref cursor in oracle sql developer stack overflow. Oracle database tips by donald burlesondecember 16, 2015 question. How to use ref cursor example a ref cursor is basically a data type. Net framework data provider for oracle supports the oracle ref cursor data type. Getting ref cursors from oracle procedure in data access. It represents a cursor or a result set in oracle database.
Ask tom question on using ref cursor oracle ask tom. Launch reports builder or, if already open, choose file. Even the oracle thin and merantdriver does it the regular way, i. Cursor expressions as arguments to functions called from sql. The primary advantage of using cursor variables is their capability to pass result sets between sub. To use these examples, you may need to create the oracle tables, and you must create a plsql package and package body. However, that said i fail to see why you having to select in one stored procedure, to put the data into a global temporary table and then just join. Net type for the ref cursor type this section discusses the following aspects of using the ref cursor data type and oraclerefcursor objects. The cursor can be opened on the server and then passed to the referenced to the same cursor among all the programs that need the cursor access. What is the difference between a normal cursor and a ref. I tried for ages, but couldnt get your example to work especially regarding the ref cursor.
But if you look carefully your code, there is actually no argument provided for this cursor once the cursor has been opened within the second inner for loop. You cannot define the same cursor more than stead you can only use it. You need to fetch the ref cursor into transient memory or persistent storage normal or global temporary table. In addition to providing the performance improvements described in earlier sections, cursor functionality now extends beyond queries, and it is integral to the design and building of applications. Using plsql ref cursors burleson oracle consulting. In essence, a ref cursor allows you to store the result of a bulk collect from a table or any plsql cursor return set into a plsql table ram array and then reference the array with the ref cursor as a pointer. Different behavior for ref cursor between oracle 10g and. For information on ref cursors, see oracle ref cursor type category.
Lines 3 and 4 define the cursor and return record used in the body. A ref cursor is a plsql data type whose value is the memory address of a query work area on the database. Returning a ref cursor based on a plsql collection amis. Different types of cursors in plsql oracle live sql. A ref cursor is a variable, defined as a cursor type, which will point to, or reference a cursor result. Plsql where current of cursor oracle consulting, oracle. Author of the oracle press book oracle soa suite 12c handbook. You can refer to these files as you complete each section of this chapter. Answer sure ref cursor is a datatype we can assign variables that data type called cursor variable,cursor variable can associate with different queries at run time,primary advantage of refcursor is we can pass result set morethan one sub program. Different from implicit and explicit cursors, a cursor variable is not tied to any specific query. Using ref cursors is one of the most powerful, flexible, and scalable ways to return query results from an oracle database to a client application a ref cursor is a plsql data type whose value is the memory address of a query work area on the database. When i execute the fetch, i get ora01001 invalid cursor. Basically, the procedure opens a reference cursor, updates a table then completes. Can you please show an example of the where current of clause in plsql.
Help need urgently for oracle cursors in k shell scripting. Ref cursor s are represented through the oraclerefcursor odp. A variable created based on such a data type is generally called a cursor variable. In the previous posts we have covered ref cursors and ref cursor examples. The oracle scotttiger schema is included with most oracle installations. Often when the ref cursors are closed oracle throws ora00600 17281 1001 when or before you terminate your session. These examples use tables that are defined in the oracle scotttiger schema. This sample shows how to call a plsql function that opens a cursor and get the cursor back as a java resultset. You need to be able to copy and optionally transform any plsql ref cursor in a uniform way across all editions of oracle database from 10g release 1 and newer. I am using oracle sql developer, but i am having an issue seeing results from a package that returns a ref cursor. It can be used to easily create simple csvs or fixedlength files. Free oracle magazine subscriptions and oracle white papers.
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