What is the difference between ref cursor and cursor?
A cursor is really any SQL statement that runs DML (select, insert, update, delete) on your database. A ref cursor is a pointer to a result set. This is normally used to open a query on the database server, then leave it up to the client to fetch the result it needs.
Does ref cursor increase performance?
The next performance-related advantage of a regular cursor is also an ease-of-use feature. A regular cursor can implicitly array-fetch 100 rows at a time, whereas a ref cursor must use explicit array fetching. In other words, a regular cursor can more efficiently retrieve data by using significantly less code.
When should we use ref cursor in Oracle?
Using REF CURSOR s 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.
What is ref cursor and its typeS?
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 advantage of ref cursor in Oracle?
Answer: A ref cursor is a PL/SQL variable, defined as a cursor type, which will point to, or reference a cursor result. 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. The ref cursor can be assigned to other ref cursor variables.
What is cursor types of cursor and diff b W cursors?
Cursors can be broadly classified into Implicit Cursors and Explicit Cursors. Implicit cursors are automatically created when select statements are executed. Explicit cursors needs to be defined explicitly by the user by providing a name. They are capable of fetching a single row at a time.
Which is faster in or exists?
The EXISTS clause is much faster than IN when the subquery results is very large. Conversely, the IN clause is faster than EXISTS when the subquery results is very small. Also, the IN clause can’t compare anything with NULL values, but the EXISTS clause can compare everything with NULLs.
Which cursor is faster in Oracle?
implicit cursors
The short answer is that implicit cursors are faster and result in much neater code so there are very few cases where you need to resort to explicit cursors.
Can we use Isopen attribute with implicit cursor?
%ISOPEN Attribute: For Implicit Cursors, always the result is False. The reason is Oracle closes immediately after executing the DML result. Hence the result is FALSE.
What is weak ref cursor?
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.
What is the difference between REF CURSOR and regular cursor?
2) A ref cursor is defined at runtime and can be opened dynamically but a regular cursor is static and defined at compile time. 3) A ref cursor can be passed to another PL/SQL routine (function or procedure) or returned to a client. A regular cursor cannot be returned to a client application and must be consumed within same routine.
Does NET Framework support Oracle ref cursors?
Oracle REF CURSORs. The .NET Framework Data Provider for Oracle supports the Oracle REF CURSOR data type. When using the data provider to work with Oracle REF CURSORs, you should consider the following behaviors. Some behaviors differ from those of the Microsoft OLE DB Provider for Oracle (MSDAORA).
What is the difference between the Oracle cursor and SQL Server cursor?
The Oracle cursor is a memory space for handling data and even optimizing performance. A SQL Server cursor is a mechanism for stepping through a result set one row at a time. These are two totally different functions.
What is a normal cursor?
Normal Cursor : The cursor definition is static. only one and static definition to the cursor. You cannot define the same cursor more than once.instead you can only use it.