How do I open a cursor in PL SQL?
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 are cursor attributes in PL SQL?
Each cursor has a set of attributes that enables an application program to test the state of the cursor. These attributes are %ISOPEN, %FOUND, %NOTFOUND, and %ROWCOUNT. This attribute is used to determine whether a cursor is in the open state.
Can we reopen a cursor in Plsql?
Although you must close a cursor before you can reopen it, PL/SQL need not reparse the associated SELECT statement. If you close, then immediately reopen the cursor, a reparse is definitely not needed. Rows in the result set are not retrieved when the OPEN statement is executed. The FETCH statement retrieves the rows.
What occurs when cursor is opened?
When a cursor is opened, the following things happen: The values of the bind variables are examined. Based on the values of the bind variables, the active set (the query result) is determined. The active set pointer is set to the first row.
How do I open my cursor?
OPEN cursor-name ; To open the cursor in the ORDER BY clause, use the following: DECLARE revenue CURSOR FOR SELECT Model, Units, Price, Units * Price AS ExtPrice FROM TRANSDETAIL ORDER BY Model, ExtPrice DESC ; OPEN revenue ; You can’t fetch rows from a cursor until you open the cursor.
Which type of cursor is automatically declared?
21) Which type of cursor is automatically declared by Oracle every time an SQL statement is executed? Explanation: The implicit cursor are automatically created.
Is open in cursor?
If a cursor is open, cursor_name%ISOPEN returns TRUE ; otherwise, it returns FALSE . A cursor attribute that can be appended to the name of a cursor or cursor variable. Before the first fetch from an open cursor, cursor_name%NOTFOUND returns NULL .
What are the types of cursor?
There are 2 types of Cursors: Implicit Cursors, and Explicit Cursors. These are explained as following below. Implicit Cursors: Implicit Cursors are also known as Default Cursors of SQL SERVER.
Can we declare cursor inside begin?
In general, yes you can, you just nest another execution block inside your current one…
What is the syntax for opening a bound cursor?
OPEN unbound_cursorvar [ [ NO ] SCROLL ] FOR EXECUTE query_string [ USING expression [, … ] ]; The cursor variable is opened and given the specified query to execute. The cursor cannot be open already, and it must have been declared as an unbound cursor variable (that is, as a simple refcursor variable).
Can we pass cursor as parameter?
No, you can’t pass a static cursor as a parameter.
Can we use where clause in cursor?
A positioned update using a WHERE CURRENT OF clause updates the single row at the current position of the cursor. … In this structure, the cursor will loop through each row retrieved from the SELECT query in the cursor declaration.
Is cursor a view on a table?
4 Answers. A cursor is defined and used within the scope of a stored procedure (it is used with PL/SQL). On the other hand, a view is a database object (similar to a table), which can be used even outside of stored procedures as well, as in queries (it can be used with both SQL and PL/SQL).
What is the use of cursor in Android?
A Cursor represents the result of a query and basically points to one row of the query result. This way Android can buffer the query results efficiently; as it does not have to load all data into memory.