What is the difference between SELECT and cursor in PL SQL?

CURSOR is mainly used to extract data in segments or chunks from the DB table. Conversely for the SELECT statement and its variants, data is directly copied into a data object in the ABAP memory.

What is difference between cursor and procedure?

A function or procedure is a set of instructions to perform some task. A cursor is an array that can stores the result set of a query. Stored procedures are pre-compiled objects and executes as bulk of statements, whereas cursors are used to execute row by row.

What is cursor SELECT?

The cursor SELECT statement is specified as part of a DECLARE CURSOR statement. The cursor SELECT statement specifies the data to be retrieved by the cursor. When executed, the DECLARE CURSOR statement does not perform the retrieval; the retrieval occurs when the cursor is opened.

What is cursor used for 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.

What is the difference between cursor fetch and for loop?

Open the explicit cursor (with the OPEN statement), fetch rows from the result set (with the FETCH statement), and close the explicit cursor (with the CLOSE statement). The cursor FOR LOOP statement lets you run a SELECT statement and then immediately loop through the rows of the result set.

What is cursor and index in SQL?

In SQL, a cursor can be defined as a tool used widely to define a particular set of results. This result can be a set of data rows. A cursor is basically used to solve complex logic and works on a row by row manner. Index, on the other hand, has the main function of retrieving data from tables much quicker.

What is difference between trigger and cursor?

A cursor is activated and thus created in response to any SQL statement. A trigger is executed in response to a DDL statement, DML statement or any database operation.

What is cursor example?

Oracle creates a memory area, known as the context area, for processing an SQL statement, which contains all the information needed for processing the statement; for example, the number of rows processed, etc. A cursor is a pointer to this context area. A cursor holds the rows (one or more) returned by a SQL statement.

What is the use of cursor?

Cursors are used by database programmers to process individual rows returned by database system queries. Cursors enable manipulation of whole result sets at once. In this scenario, a cursor enables the sequential processing of rows in a result set.

What is the use of cursor explain with example?

Cursor is a Temporary Memory or Temporary Work Station. It is Allocated by Database Server at the Time of Performing DML(Data Manipulation Language) operations on Table by User. Cursors are used to store Database Tables. There are 2 types of Cursors: Implicit Cursors, and Explicit Cursors.

When would you use a cursor?

Use of Cursor 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. Cursors are used when the user needs to update records in a singleton fashion or in a row by row manner, in a database table.

What is difference between cursor and loop?

SQL While loop and cursor are the most common approach to repeat a statement on condition-based or determined limits. Loop and cursor can be utilized in a circumstance to deal with row-based processing in T-SQL. While SQL While loop is quicker than a cursor, reason found that cursor is defined by DECLARE CURSOR.

How do you use the cursors in a SELECT statement?

A SELECT statement makes use of the CURSORS implicitly to fetch the data from the database. Using CURSOR: The CURSOR follows a three stage process of getting data from the database. The process is OPEN CURSOR…FETCH CURSOR…CLOSE CURSOR.

What is the use of use of a cursor in SQL?

CURSOR decouples the process of SELECT statement and INTO clause. This is done by opening a cursor for a select statement. This is used to extract data in chunks from the database table. Only after getting the complete data, the data is stored in the target area

What is the difference between curlsor and SELECT statement in MySQL?

CURSOR is mainly used to extract data in segments or chunks from the DB table. Conversely for the SELECT statement and its variants, data is directly copied into a data object in the ABAP memory.

What is SELECT statement in SQL?

SELECT statement is an Open SQL statement for reading data from one or more database tables, classic views, or CDS views. The SELECT statement reads the data directly into the target area specified in the INTO clause.