![]() ![]() You should not declare the cursor before any variable declaration. DECLARE cursorname CURSOR FOR SELECTstatement DECLARE: First, declare a cursor with a name associated with a SELECT statement. The Cursor in MySQL performs four actions, which are:ġ. Fetching the cursor to retrieve the data into local variables.Opening the cursor to establish the result set.Declaring the cursor to define a result set.Syntax and steps for an explicit cursor: CURSOR cursorname IS selectstatement Attributes: SQL%FOUND, SQL%NOTFOUND, %ISOPEN, %ROWCOUNT.We create it on SELECT statements that return multiple records.We define it in the declaration area of the SQL block.User-defined cursors help to gain more control over the context part.Associated with INSERT, UPDATE, and DELETE types of DML operation statements.Users or programmers cannot control the information or programs in it.Oracle automatically creates a cursor when executing SQL if no explicit cursor is specified.A cursor holds a set of rows known as an Active set.Ĭursors are of two types in MySQL: 1. When you execute an SQL statement, the system generates a temporary workspace in the memory known as the cursor. ![]() An asensitive cursor points to the actual data, whereas an insensitive cursor uses a provisional copy of the data. Asensitive: Cursors are of two kinds: asensitive and insensitive cursors.It is not possible to fetch rows in reverse order, and you cannot skip or jump to a specific row in the result set. Non-Scrollable: In MySQL, you can only fetch rows in the order they appear in the SELECT statement.Read-Only: Using the cursor, you cannot modify any data in the primary table. ![]()
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