After a cursor is closed, it cannot be reused without being opened again. 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. To use a SQL cursor, you first must declare its existence to the DBMS. A cursor is a temporary work area created in the system memory when a SQL statement is executed. Also, if the cursor is defined as SCROLLABLE we can even move back to the previous row. Another reason I don't like cursors is clarity. 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 … If you do not explicitly close a cursor, MySQL will close it automatically when the END statement is reached. Both implicit and explicit cursors have the same functionality, but they differ in the way they are accessed. Therefore, cursors are used as to speed the processing time of queries in large databases. I think cursors are still a bad choice unless you understand enough about them to justify their use in limited circumstances. The following picture describes steps that you need to follow when you work with a PL/SQL cursor: PL/SQL Cursor. 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. Let's take an example to demonstrate the use of explicit cursor. Working with PL/SQL Cursor. The set of rows the cursor holds is referred to as the active set. PL/SQL Explicit Cursor Example. A DECLARE CURSOR statement has the following syntax: PL/SQL controls the context area through a Cursor. Explicit cursors are defined by programmers to gain more control over the context area. Programmers are allowed to create named context area to execute their DML operations to get more control over it. It is an essential component in stored procedures. Here is an updated version of the previous example: 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. A PL/SQL cursor is a pointer that points to the result set of an SQL query against database tables. It is defined in the declaration section of the PL/SQL block. There are two types of cursors in PL/SQL : Implicit cursors. 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. 1. A cursor in SQL is a temporary work area created in system memory when a SQL statement is executed. A cursor holds the rows (one or more) returned by a SQL statement. Explicit Cursor. You do this with a DECLARE CURSOR statement. The cursor block is so ugly that it's difficult to use in a clear and effective way. However, a cursor does not need to be declared again to be used; an OPEN statement is sufficient. Explicit cursors. The explicit cursor should be defined in the declaration section of the PL/SQL block, and it is created for the 'SELECT' … PL/SQL controls the context area through a cursor. Example Database Cursors in SQL. A cursor is a select statement, defined in the declaration section in MySQL.. Syntax The set of rows the cursor holds is called the active set. Mysql cursor issue? MySQL Cursor. Following are the steps for creating a cursor. Let’s examine each step in greater detail. A cursor can hold more than one row, but can process only one row at a time. In MySQL, Cursor can also be created. It is created on a SELECT statement which returns more than one row. SQL is a set based language--that's what it does best. Declare Cursor. A cursor contains information on a select statement and the rows of data accessed by it. By Allen G. Taylor . 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