This allows you to store select statements in the database and reference them from sqlplus. Ask tom returning cursor from stored procedure using. February 20, 2012 my copy of the oracle database 11gr2 performance. Because jdbc does not support a cursor variable data type, the oracle driver returns ref cursor output parameters and return values to the application as result sets. A ref cursor can have an arbitrary query associated with it. Refcursor bind variables can also be used to reference plsql cursor variables in stored procedures. I am trying to write a generic function that will call a stored procedure name passed in as varchar2 parameter that returns a ref cursor as an out parameter. The name ref cursor can be confusing because a ref cursor variable is not a cursor, but a variable that points to a cursor, similar to a char datatype in the c language. However, sometimes, you may want to process a data set on a row by row basis. The ref cursor variable is not a cursor, but a variable that points to a cursor.
In the end, im putting the ref cursor data into a data set in my vs. Net type for the ref cursor type this section discusses the following aspects of using the ref cursor datatype and oraclerefcursor objects obtaining an oraclerefcursor object. Cursor variables are cursors opened by a plsql routine and fetched from by another application or plsql routine the cursor variables are opened with the privileges of the owner of the procedure and behave just like they were completely contained within the plsql routine. Ask tom return values from a plsql table into a ref cursor.
Plsql procedure returning a refcursor with embedded cursors june 28, 2004 7. Ask tom plsql procedure returning a refcursor with. We have already seen how to return a table from a function on the below post. How to return a ref cursor from a procedure pl sql. You cannot position a record pointer inside the ref cursor to point to random records in the result set. In essence, a ref cursor is a pointer or a handle to a result set on the database. A fetch statement retrieves rows one at a time from the result set of a multirow. This example executes a plsql stored procedure that returns a ref cursor parameter, and reads the value as an oracledatareader. The cursor variable is specified as an in out parameter so that the result set is made available to the caller of the procedure. Before assigning a cursor variable, a cursor type must be defined. The application would appear to be faster to the end user.
Stronglytyped cursor variables of the ref cursor type require a result set. Hi tom, it is my first question on your site and i hope you can help me. However, you need to set the return type for it manually. The ref cursor is a datatype in the oracle plsql language. Jun 09, 2009 returning multiple ref cursors from oracle only not using daab. Now, in this post, we will define and open a ref cursor variable and then pass it to a stored procedure. Because jdbc does not support a cursor variable data type, the oracle driver returns ref cursor output parameters and return values to. Procedure that outputs a dynamic plsql cursor question. Defining cursor variables ref cursor return clause. The ref cursor is a data type in the oracle pl sql language.
Yes i see that now, i assumed the function returned the ref cursor since you originally said i would like to execute this function and return the result set of the refcursor in sqlplus. Getting result sets from oracle stored procedures via jdbc. Returning multiple ref cursors from oracle only not using daab. We can now write a stored procedure that returns a ref cursor, that in jdbc we can process as a result set. Retrieving data from multiple ref cursors using an oracledatareader.
Returning a ref cursor from a oracle function stack overflow. In essence, an oracle 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. Directly executing a query is slower than returning a refcursor. A refcursor bind variable is passed as a parameter to a procedure. 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. Different from implicit and explicit cursors, a cursor variable is not tied to any specific query. This example demonstrates how to define and open a ref cursor variable, and then pass it as a procedure parameter. Plsql cursor variables with ref cursor oracle tutorial. The return type of this static ref cursor is usually the record structure of a table, view, nested table type, varray type, or a userdefined record type, thus restricting it to return a single structure making it more specific and less prone to. Ive created an html form where the user can enter any combination of three values to retrieve results from the wine table. To reprint the results, the plsql block must be executed again before using print. Free oracle magazine subscriptions and oracle white papers. Using ref cursor s is one of the most powerful, flexible, and scalable ways to return query results from an oracle database. The oracle driver converts the ref cursor data to a result set that can be returned using getresultset or getmoreresults.
The ref cursor is a data type in the oracle plsql language. In the end, im putting the ref cursor data into a data. Replace the returntyperef cursor attribute with the devart. 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. When a refcursor is defined with a return type, it is called as a strongly typed static refcursor. Parameter direction stronglytyped ref cursor weaklytyped ref cursor. With a numeric for loop, the body of the loop executes once for every integer value between the low and high values specified in the range. This example executes a plsql stored procedure that returns two ref cursor parameters, and reads the values using an oracledatareader. The variables must match both in number and positionally the columns listed in the ref cursor open statement. Ok, so here is the answer to your original question. In essence, an oracle ref cursor allows you to store the result of a bulk collect from a table or any pl sql cursor return set into a pl sql table ram array and then. The example below uses a ref cursor to return a subset of the records in the emp table. One can use a ref cursor as target of an assignment, and it can be passed as parameter to other program units. Example 319 using refcursor variables in stored procedures.
Now we will examine how ref cursor examples are tested. To reprint the results, the pl sql block must be executed again before using print. Can i return ref cursor from plsql function in oracle. Java,stored procedure,oracle,stored procedures and java. However, there might be a situation where id like to return a null ref cursor. Cursor variables are cursors opened by a pl sql routine and fetched from by another application or pl sql routine the cursor variables are opened with the privileges of the owner of the procedure and behave just like they were completely contained within the pl sql routine. The return type of this static refcursor is usually the record structure of a table, view, nested table type, varray type, or a userdefined record type, thus restricting it to return a single structure making it more specific and less prone to. Replace the returntype ref cursor attribute with the devart. I have defined the simple package in oracle below, and want to call the function or procedure and iterate through the rows returned. Normally a cursor is a static thing, it points to a query. Also the data types must either match or be compatible. 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. Returning multiple ref cursors from oracle using daab. Display refcursor results through sqlplus oracle faq.
With a cursor for loop, the body of the loop is executed for each row returned by the query. The data represented by the ref cursor is accessed in a forwardonly, serial manner. Meaning that a cursor variable can be opened for any query. The plsql block must return an opened ref cursor either by executing an open for select statement or by invoking a function or procedure. Learn more returning a ref cursor from a oracle function.
Using plsql stored procedures and ref cursors oracle docs. There are two steps required to create a cursor variable. I had implemented a procedure that execute dynamic procedure and now im trying to write a function that return a ref cursor of a dynamic sql to force the developer team to use bind variable every time, but i want to know if i do it as only way i can do or if i can do it better, i use your example of context. Strong plsql ref cursors burleson oracle consulting. In oracle, i have a table called wine and a stored procedure that outputs a cursor based on the wine table. The return value of a strongly typed ref cursor must be a record which can be defined using the %rowtype and %type attributes or as a record structure. Click here to read how to return table from a function. 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. Returning a ref cursor from a procedure pl sql this example demonstrates how to define and open a ref cursor variable, and then pass it as a procedure parameter. When a ref cursor is defined with a return type, it is called as a strongly typed static ref cursor. With a ref cursor the client gets to get at the data right away dont have to fetch the last row before they see the first row. If i was to return an array i would have to fetch all of the rows on the plsql side. Ref cursor is the oracle data type for a cursor variable. A cursor variable is a variable that references to a cursor.
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 pl sql data type whose value is the memory address of a query work area on the database. It represents a cursor or a result set in oracle database. You create and return a ref cursor inside a plsql code block. The cursor for loop is an elegant and natural extension of the numeric for loop in plsql. A ref cursor that specifies a specific return type. Run operations using ref cursors in oracle database using. How to test a function returning a ref cursor from sqlplus. Is there a way to return a ref cursor from a stored function or procedure and iterate through it.
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