cursor sql

Original: http://ntk2006.blog.sohu.com/135331235.html Cursor ConceptCursors provide a flexible way to retrieve and operate data from tables. cursors are mainly used on servers to process SQL statements sent from clients to servers, or data

I. cursor Recognition Cursor allows you to access the result set returned by SQL Server row by row.A major reason for using cursor is to convert the set operation into a single record processing method.After retrieving data from a database using

Oracle Database: PL/SQL cursor overview, oracleplI. cursor Concept Literally, it refers to a swimming cursor, which is a handle or pointer pointing to the context area. When performing the CRUD operation in the PL/SQL block, ORACLE allocates a

CursorA cursor is a data buffer opened by the system for the user, which holds the results of the SQL statement execution. Each cursor area has a name that allows the user to retrieve the record from the cursor one at a-and assign it to the main

Cursor is a complex concept in the database field, because it contains shared cursor and session cursor. The two have different concepts and forms.The concept of shared cursor is easy to confuse with the cursor defined in SQL statements. This

Cursor and dynamic SQL, cursor dynamic SQL Cursor type: Static cursor (the cursor is statically bound to a select statement during compilation. This cursor can only act on one query statement) and dynamic cursors (that is, we want our query

Cursor is a method for processing data. To view or process data in a result set, A cursor provides the ability to forward or backward data in a result set by one or more rows. We can use a cursor as a pointer, which can specify any position in the

1. Define the cursor DefinitionThe core of a cursor statement is to define a cursor Identification name and associate it with a query statement. The DECLARE statement is used to DECLARE the cursor. It defines the data set stored in the cursor

Today, we will briefly summarize the usage of cursor in PL/SQL. Cursor category: -- Explicit cursor-- Static cursor | | -- Implicit cursorCursor |-- Strong type (Restriction), specifying the return type-- Dynamic Cursor -- ref cursor |-- Weak type

A MS-SQL cursor is a temporary database object that is used to rotate copies of data rows stored in a system Permanent Table, it can also point to the data row stored in the system Permanent Table. A cursor provides you with a method to operate data