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This article describes how to use the PageSize, PageCount, and Absolute
Page properties of an ADO recordset and what cursor types must be used to
get Recordset Paging to work. Every once in a while you may be comming
across the task of displaying a large number of records in ASP pages. The
good example is displaying the results of a search. Most of the time you
do not know the number of records that you have to display in advance. In
addition to this, as the usage of the application growth the size of the
database will grow accordingly. That leaves you as well as anyone with the
similar application requirements no other choice, but to develop some kind
of algorithm to display records in the smaller portion of pages.The ADO
Recordset object is used to hold a set of records from a database table.
A Recordset object consist of records and columns (fields).
In ADO, this object is the most important and the one used most often
to manipulate data from a database.
Everyone is familiar with the way search results are displayed by Internet
search engines. You get the first page of results that are limited to
some number of records and some nearest links to go to the first, previous,
next or the last page. Some sites give you the ability to go directly
to specific page number, some use a mixture of both.
The second page of the article should be capable of following the following
rule :-
- Receive the Keyword that user have entered.
- Search the database for records containing Keyword.
- Display a page of resulting records.
- Provide user with some navigation links to display more pages
of results if needed.
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Recordset objects can support Two Types of Updating :-
- Immediate updating :- All changes are written immediately
to the database once you call the Update method.
- Batch updating :-The provider will cache multiple changes
and then send them to the database with the UpdateBatch method.
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In ADO there are Four Different Cursor types defined :-
- Dynamic cursor :- Allows you to see additions, changes,
and deletions by other users.
- Keyset cursor :- Like a dynamic cursor, except that you
cannot see additions by other users, and it prevents access to
records that other users have deleted. Data changes by other users
will still be visible.
- Static cursor :- Provides a static copy of a recordset
for you to use to find data or generate reports. Additions, changes,
or deletions by other users will not be visible. This is the only
type of cursor allowed when you open a client-side Recordset object.
- Forward-only cursor :- Allows you to only scroll forward
through the Recordset. Additions, changes, or deletions by other
users will not be visible.
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Note :- Not all providers support all methods or properties of
the Recordset object.
The Methods of the Recordset are as follows :-
| Method |
Description |
| AddNew |
Creates a new record. |
| Cancel |
Cancels an execution. |
| CancelBatch |
Cancels a batch update. |
| CancelUpdate |
Cancels changes made to a record of a Recordset object. |
| Clone |
Creates a duplicate of an existing Recordset. |
| Close |
Closes a Recordset. |
| CompareBookmarks |
Compares two bookmarks. |
| Delete |
Deletes a record or a group of records. |
| Find |
Searches for a record in a Recordset that satisfies
a specified criteria. |
| GetRows |
Copies multiple records from a Recordset object into
a two-dimensional array. |
| GetString |
Returns a Recordset as a string. |
| Move |
Moves the record pointer in a Recordset object. |
| MoveFirst |
Moves the record pointer to the first record. |
| MoveLast |
Moves the record pointer to the last record |
| MoveNext |
Moves the record pointer to the next record
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MovePrevious |
Moves the record pointer to the previous record |
| NextRecordset |
Clears the current Recordset object and returns the
next Recordset object by looping through a series of commands |
| Open |
Opens a database element that gives you access to records
in a table, the results of a query, or to a saved Recordset |
| Requery |
Updates the data in a Recordset by re-executing the
query that made the original Recordset |
| Resync |
Refreshes the data in the current Recordset from the
original database |
| Save |
Saves a Recordset object to a file or a Stream object
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| Seek |
Searches the index of a Recordset to find a record that
matches the specified values |
| Supports |
Returns a boolean value that defines
whether or not a Recordset object supports a specific type of functionality
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| Update |
Saves all changes made to a single record in a Recordset
object |
| UpdateBatch |
Saves all changes in a Recordset to the database. Used
when working in batch update mode |
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