Basic Oracle cursor and basic oracle cursor
I. cursorThe cursor is used to process the multi-row records retrieved from the database (using the SELECT statement ). With the cursor, the program can process and traverse the entire record set returned
server| Cursor Sql-server Declaration cursor
Each cursor must have four components, these four key parts must conform to the following order;
1.DECLARE Cursors
2.OPEN Cursors
3. Fetch information from a cursor
4.CLOSE or deallocate cursors
Usually
When Oracle Database executes a SQL statement, it stores the result set and processing information in an unnamedprivate SQ L area. A pointer to the unnamed area, called acursor, lets youretrieve the rows of the result set one at a time.Cursor
One: Understanding CursorsCursor It enables the user to access the result set returned by SQL Server on a row-by-line basis.One of the main reasons for using cursors is to convert the set operation to a single record processing mode.When data is
I. Classification of Cursors
The Oracle database provides two types of cursors, static and dynamic, while static cursors are divided into hermit cursors and explicit cursors, and dynamic cursors are classified as weak and strongly typed. Second,
1. Why cursors are used: one of the main reasons for using cursors is to convert the set operation into a single record processing mode. When data is retrieved from a database in SQL language, the result is placed in an area of memory, and the
There are two types of cursors:
Display cursor, implicit cursor
Cursor is used to display the cursor... the is command defines the cursor, which can process multiple records returned by the query statement (select), while the implicit cursor is
An Oracle cursor is divided into a display cursor and an implicit cursor.
Display cursor (Explicit Cursor): A cursor defined in a PL/SQL program, used for querying, is called a display cursor.Implicit cursors (implicit Cursor): A cursor that is
The cursor is evil!
In relational databases, our thinking about queries is set-oriented. The cursor breaks this rule, and the cursor makes the way we think is done on a line-by-row basis. For developers of Class C, this is a more comfortable way to
CURSOR is also called a CURSOR. It is often used in relational databases. In PLSQL programs, you can use CURSOR and SELECT to query and read data in tables or views row by row.
CURSOR is also called a CURSOR. It is often used in relational databases.
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