The callablestatement object is cast to oraclecallablestatement to use the getcursor method, which is an oracle extension to the standard jdbc api, and returns the ref cursor into a resultset object. I have a forms 6i that makes a call to the function, with the intent of fetching the data associated with the ref cursor. Cursor variables are defined using a ref cursor type. When i execute the fetch, i get ora01001 invalid cursor.
Return values from a plsql table into a ref cursor. This example executes a plsql stored procedure that returns two ref cursor parameters, and fills a dataset with the rows that are returned. Return a list of cursors which correspond to implicit results made available from a plsql block or procedure without the use of out ref cursor parameters. To use these examples, you may need to create the oracle tables, and you must create a plsql package and package body. For this introduction to the php language and the php oci8 extension which accesses the oracle database, no php framework or abstraction layer is used. Building a paper report with ref cursors oracle docs. I cant do a standard select this doesnt work open tunnelcrs for select gw1, gw2 from a.
I see no need for opening a ref cursor, dynamically or otherwise, so i would just use a regular cursor for loop. Stored procedures can accept or return cursor variables of the ref cursor category. Run operations using ref cursors in oracle database using. Or you can use a regular cursor for loop, which implicitly opens a cursor, not a ref cursor. Over the years i have experimented with a lot else too, even resorting to thoroughly rtfm from oracle. The primary advantage of using cursor variables is their capability to pass result sets between sub. It represents a cursor or a result set in oracle database. The oracle docs specify that the open statement only identifies the result set, but does not retrieve the rows, which happens only with every call to the fetch statement.
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. A cursor variable can be associated with different queries at runtime. Whenever oracle executes an sql statement such as select into, insert, update, and delete, it creates an implicit cursor. A hybrid pdf odf file is a pdf file that contains an embedded odf source file. Hybrid pdf odf files will be opened in as an odf file without any layout changes. The function creates dynamic sql and initiates the open of the cursor. Demos, syntax, and example code of oracle plsql strongly typed and weakly typed ref cursors. Fusion middleware oracle reports users guide to building reports. How cursor variables are defined is the topic of the next section. The long and long raw sql types and ref cursor type category have no oracle. The steps in this section will help you create package specs that define ref cursors to define a ref cursor type. Oracle database sql language reference oracle database plsql language reference.
Oracle recommends the use of standard jdbc types or java types whenever possible. 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. When using the data provider to work with oracle ref cursors, you should consider the following behaviors. 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. Plsql ref cursor and oraclerefcursor oracle help center. This output is equivalent to a database cursor or a jdbc result set.
We will now look at how we can use visual basic to call our procedures and read the records stored in the ref cursor. Can i see some examples of working ref cursor examples, especially passing a ref. Part 12 in a series of articles on understanding and using plsql. Select from tableoracle ref cursor woodward informatics ltd. Because a ref cursor is a pointer to memory on the server that is returned to the client, the actual data contained in the ref cursor is not initially returned to the client.
The cursor variable is specified as an in out parameter so that the result set is made available to the caller of the procedure. This variable is then looped for processing the returned result set as shown in. The steps in this section will help you create package specs that define ref cursors. The callablestatement object is cast to an oraclecallablestatement object to use the getcursor method, which is an oracle extension to the standard jdbc api, and returns the ref cursor into a resultset object. How to use ref cursor example a ref cursor is basically a data type. A ref cursor is an oracle plsql data type that represents a pointer to a result set in the oracle database. Say the business requirement changes so that the data should be displayed in a different order. Oracle database tips by donald burlesonapril 18, 2015. A ref cursor essentially encapsulates the results of a query. The callable statement is executed, returning the ref cursor. Cursors returned in this fashion should not be closed.
Free oracle magazine subscriptions and oracle white papers. A ref cursor that specifies a specific return type. I am using several package functions to return ref cursors to a java front end. The callable statement is run, returning the ref cursor. Run operations using ref cursors in oracle database using the wcf service model. Plsql cursor by practical examples oracle tutorial. A ref cursor involves an additional database round trip. 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. Strong plsql ref cursors burleson oracle consulting. A ref cursor is a plsql data type whose value is the memory address of a query work area on the database. Hence you close a ref cursor after you fetch from it. The refcursor declared in this programs scope is never opened as when it is assigned to the same refcursors variable in the out parameter, the information of the cursor variable from the server program is copied into this variable, thus making it its alias. Jun 27, 2012 i doubt something like this would be feasible.
The data is stored in variables or fields that correspond to the columns selected by the query. One can use a ref cursor as target of an assignment, and it can be passed as parameter to other program units. To read more about ref cursor i have created a package to explain few different ref cursor examples. I have a ref cursor defined as an out parameter and i am trying to get a receiving plsql to accept the ref cursor. You can fetch rows one at a time, several at a time, or all at once. I wrote a stored procedure using ref cursor,and be a data set of reporting service. How to use a ref cursor to pass a varray and disassemble it on the receiving end. The contents of the plsql table are not returnable by a single sql statement. 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. You have to pass the type of ref cursor to procedure that it is expecting, you are simply passing the wrong type. Net framework data provider for oracle supports the oracle ref cursor data type.
Its a great solution if you have to convert calls to oracle stored procedure that return collections from classic asp during the o. If the cursor is moved to a package, you will have the now necessary close already in place. Using plsql stored procedures and ref cursors oracle docs. If you lose your result set that indicates you are not done with the ref cursor. A variable created based on such a data type is generally called a cursor variable. The ref cursor can be assigned to other ref cursor variables.
I cant close ref cusor becasue of losing my result set. Defining cursor variables ref cursor return clause. There he asked one question as what is the difference between cursor and ref cursor, and when would you appropriately use each of these. A cursor is a pointer that points to a result of a query. The problem is when there are no rows in the cursor suppose the table doesnt have any rows and we are reading it into a cursor and from the front end i.
This is a step oracle database performs with the selectinto statement. You can open a ref cursor, dynamically or not, and fetch from it within a loop. Strongly typed the ref cursor type is restricted to an individual return type using the return clause. Hi tom, feels good that i got a chance to ask you a question. And if it is local, then including a close statement will also show other developers and your manager that you are paying attention. To create a ref cursor query, you first create a package spec that defines the ref cursor. 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. When a refcursor is defined with a return type, it is called as a strongly typed static refcursor.
This attribute is an extension to the db api definition but it is mentioned in pep 249 as an optional extension. Using plsql stored procedures and ref cursors oracle. There are two steps required to create a cursor variable. See the oracle documentation for more information about the statement cache. Ref cursor, then, is a category of data types, rather than a particular data type. Users without this extension can open the pdf part of the hybrid file with their pdf viewer. A ref cursor is a variable, defined as a cursor type, which will point to, or reference a cursor result. The cursor for loop is an elegant and natural extension of the numeric for loop in plsql. Until oracle has retrieved all the rows then by definition it does not have an accurate record of how many there are. Feb 17, 2010 how to use ref cursor example a ref cursor is basically a data type. The fetch statement retrieves rows of data from the result set of a multirow query. I am using oracle sql developer, but i am having an issue seeing results from a package that returns a ref cursor. Ask tom difference between cursor and a ref cursor oracle. Strong plsql ref cursors oracle plsql tips by boobal ganesan.
Plsql procedural language for sql is oracle corporations procedural extension for sql. 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 ref cursor in oracle sql developer stack overflow. Although this reduces the chances of runtime errors. You have to pass the type of ref cursor to procedure that it. Developers and dbas get help from oracle experts on. 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. In essence, a ref cursor is a pointer or a handle to a result set on the database. Returning ado resultsets using plsql and cursor variables. Run operations using ref cursors in oracle database using the. Using ref cursor s is one of the most powerful, flexible, and scalable ways to return query results from an oracle database.
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