What is the use of cursor in Plsql?
The ‘Cursor’ is the PL/SQL construct that allows the user to name the work area and access the stored information in it. The major function of a cursor is to retrieve data, one row at a time, from a result set, unlike the SQL commands which operate on all the rows in the result set at one time.
What is PL SQL PDF?
PL/SQL is a combination of SQL along with the procedural features of programming languages. It was developed by Oracle Corporation in the early 90’s to enhance the capabilities of SQL. PL/SQL is one of three key programming languages embedded in the Oracle Database, along with SQL itself and Java.
How many types of cursors are available in PL SQL?
A cursor is a pointer that points to a result of a query. PL/SQL has two types of cursors: implicit cursors and explicit cursors.
What is cursor exception Plsql?
An exception is a PL/SQL error that is raised during program execution, either implicitly by TimesTen or explicitly by your program. Handle an exception by trapping it with a handler or propagating it to the calling environment.
Why do we need cursors in SQL?
In SQL procedures, a cursor make it possible to define a result set (a set of data rows) and perform complex logic on a row by row basis. By using the same mechanics, an SQL procedure can also define a result set and return it directly to the caller of the SQL procedure or to a client application.
Which of the following is true about PL SQL cursors?
Q 24 – Which of the following is true about PL/SQL cursors? A – Explicit cursors are automatically created by Oracle. B – Implicit cursors are programmer defined cursors. C – The most recent implicit cursor is called the SQL cursor, and has the attributes like %FOUND, %ISOPEN, %NOTFOUND, and %ROWCOUNT.
What are PL SQL cursor exceptions?
What are cursors and its types in SQL?
Microsoft SQL Server supports the following 4 types of cursors.
- STATIC CURSOR. A static cursor populates the result set during cursor creation and the query result is cached for the lifetime of the cursor.
- FAST_FORWARD. This is the default type of cursor.
What are the types of cursors in SQL?
SQL Server supports three cursor implementations.
- Transact-SQL cursors. Transact-SQL cursors are based on the DECLARE CURSOR syntax and used mainly in Transact-SQL scripts, stored procedures, and triggers.
- Application programming interface (API) server cursors.
- Client cursors.
How do you create a cursor in SQL?
Follow these steps to create a cursor: Associate a cursor with a resultSet of a T-SQL statement, and define the characteristics of the cursor, such as how the rows are going to be retrieved, and so forth. Execute the T-SQL statement to populate the cursor. Retrieve the rows in the cursor.
What is open cursor in SQL?
Open A Cursor is opened and populated by executing the SQL statement defined by the cursor. Fetch When cursor is opened, rows can be fetched from the cursor one by one or in a block to do data manipulation.
What is the cursor variable in SQL?
Cursor variables (PL/SQL) A cursor variable is a cursor that contains a pointer to a query result set . The result set is determined by execution of the OPEN FOR statement using the cursor variable. A cursor variable, unlike a static cursor, is not associated with a particular query.
What is an open cursor in Oracle?
Open cursor is for opening the cursor. Cursor is the one which you have declared with a sql query to it. Client connections are the ones like toad, sql*plus, plsql developer etc tool which connect to the oracle database server.