It is defined in the declaration section of the PL/SQL block. Explicit Cursor. To use a SQL cursor, you first must declare its existence to the DBMS. Following are the steps for creating a cursor. A cursor contains information on a select statement and the rows of data accessed by it. I think cursors are still a bad choice unless you understand enough about them to justify their use in limited circumstances. The purpose of this example isn’t to go full detail on how to build a cursor, we’ll do that in a later article, rather, it’s to show you an example so you’ll be able to recognize them. Here is an updated version of the previous example: Explicit cursors are defined by programmers to gain more control over the context area. I have written a stored procedure which will travel's record from one table and insert those into 2-3 different tables using insert statements. Programmers are allowed to create named context area to execute their DML operations to get more control over it. Let's take an example to demonstrate the use of explicit cursor. However, a cursor does not need to be declared again to be used; an OPEN statement is sufficient. Declare Cursor. It is created on a SELECT statement which returns more than one row. A cursor can’t be used by itself in MySQL. A SQL cursor is a set of rows together with a pointer that identifies a current row. There are two types of cursors in PL/SQL : Implicit cursors. The set of rows the cursor holds is called the active set. By Allen G. Taylor . The set of rows the cursor holds is referred to as the active set. If you do not explicitly close a cursor, MySQL will close it automatically when the END statement is reached. Therefore, cursors are used as to speed the processing time of queries in large databases. A cursor in SQL is a temporary work area created in system memory when a SQL statement is executed. A DECLARE CURSOR statement has the following syntax: Let’s examine each step in greater detail. A PL/SQL cursor is a pointer that points to the result set of an SQL query against database tables. SQL is a set based language--that's what it does best. In MySQL, Cursor can also be created. Another reason I don't like cursors is clarity. 1. After a cursor is closed, it cannot be reused without being opened again. The cursor block is so ugly that it's difficult to use in a clear and effective way. The DECLARE CURSOR statement doesn’t actually cause anything to happen; it just announces the SQL cursor’s name to the DBMS and specifies what query the cursor will operate on. It is an essential component in stored procedures. PL/SQL controls the context area through a Cursor. You can name a cursor so that it could be referred to in a program to fetch and process the rows returned by the SQL … Example Database Cursors in SQL. Both implicit and explicit cursors have the same functionality, but they differ in the way they are accessed. MySQL Cursor. 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