How do I create a ref cursor in Oracle?
With a cursor variable, you simply pass the reference to that cursor. To declare a cursor variable, you use the REF CURSOR is the data type. PL/SQL has two forms of REF CURSOR typeS: strong typed and weak typed REF CURSOR . The following shows an example of a strong REF CURSOR .
What is the use of ref cursor in Oracle?
A REF CURSOR is a PL/SQL data type whose value is the memory address of a query work area on the database. In essence, a REF CURSOR is a pointer or a handle to a result set on the database. REF CURSOR s are represented through the OracleRefCursor ODP.NET class.
What is strong and weak ref cursor?
A strongly typed ref cursor always returns a known type, usually from a declared TYPE object. A weakly typed ref cursor has a return type that is dependant on the SQL statement it executes, i.e. only once the cursor is opened is the type known (at runtime).
What is weak ref CURSOR in Oracle?
When a Ref-Cursor is defined without a return type, it is called as a weakly typed dynamic Ref-Cursor. There is no dependency on its return structure, thus making it open to all SELECT statements independent of its structure.
How do I execute a CURSOR in Oracle SQL Developer?
There are four steps in using an Explicit Cursor.
- DECLARE the cursor in the Declaration section.
- OPEN the cursor in the Execution Section.
- FETCH the data from the cursor into PL/SQL variables or records in the Execution Section.
- CLOSE the cursor in the Execution Section before you end the PL/SQL Block.
What is strong ref cursor?
A ref cursor which has fixed return type is called a Strong Ref Cursor in Oracle Database. Because of fixed return type, strong ref cursors can only be used selectively. For instance with those SELECT statements that return the result whose datatype matches with the one that you have fixed during cursor’s declaration.
Why do we use bulk collect in Oracle?
Oracle PL/SQL provides the functionality of fetching the records in bulk rather than fetching one-by-one. The main advantage of using BULK COLLECT is it increases the performance by reducing the interaction between database and PL/SQL engine.
How are ref cursors used in Oracle 9i?
Since Oracle 7.3 the REF CURSOR type has been available to allow recordsets to be returned from stored procedures and functions. Oracle 9i introduced the predefined SYS_REFCURSOR type, meaning we no longer have to define our own REF CURSOR types. Related articles.
What are the types of REF CURSOR in PL / SQL?
PL/SQL has two forms of REF CURSOR typeS: strong typed and weak typed REF CURSOR. The following shows an example of a strong REF CURSOR. DECLARE TYPE customer_t IS REF CURSOR RETURN customers%ROWTYPE; c_customer customer_t;
Can a REF CURSOR be used to return a recordet?
Since Oracle 7.3 the REF CURSOR type has been available to allow recordsets to be returned from stored procedures and functions. Oracle 9i introduced the predefined SYS_REFCURSOR type, meaning we no longer have to define our own REF CURSOR types.
How is a cursor variable declared in PL / SQL?
With a cursor variable, you simply pass the reference to that cursor. To declare a cursor variable, you use the REF CURSOR is the data type. PL/SQL has two forms of REF CURSOR typeS: strong typed and weak typed REF CURSOR.