Objeto de conjunto de registros ADO
Ejemplos
Este ejemplo demuestra cómo utilizar el método GetRows.
Objeto de conjunto de registros
El objeto ADO Recordset se utiliza para contener un conjunto de registros de una tabla de base de datos. Un objeto Recordset consta de registros y columnas (campos).
En ADO, este objeto es el más importante y el más utilizado para manipular datos de una base de datos.
ID de programa
set objRecordset=Server.CreateObject("ADODB.recordset")
Cuando abre un conjunto de registros por primera vez, el puntero del registro actual apuntará al primer registro y las propiedades BOF y EOF son falsas. Si no hay registros, la propiedad BOF y EOF son True.
Los objetos Recordset pueden admitir dos tipos de actualización:
- Actualización inmediata : todos los cambios se escriben inmediatamente en la base de datos una vez que llama al método Update.
- Actualización por lotes : el proveedor almacenará en caché varios cambios y luego los enviará a la base de datos con el método UpdateBatch.
En ADO hay definidos 4 tipos de cursor diferentes:
- Cursor dinámico : le permite ver las adiciones, los cambios y las eliminaciones de otros usuarios.
- Cursor de conjunto de claves: como un cursor dinámico, excepto que no puede ver las adiciones de otros usuarios y evita el acceso a los registros que otros usuarios han eliminado. Los cambios de datos realizados por otros usuarios seguirán siendo visibles.
- Cursor estático : proporciona una copia estática de un conjunto de registros para que la utilice para buscar datos o generar informes. Las adiciones, cambios o eliminaciones de otros usuarios no serán visibles. Este es el único tipo de cursor permitido cuando abre un objeto Recordset del lado del cliente.
- Cursor de solo avance : le permite desplazarse solo hacia adelante por el conjunto de registros. Las adiciones, cambios o eliminaciones de otros usuarios no serán visibles.
El tipo de cursor se puede establecer mediante la propiedad CursorType o mediante el parámetro CursorType en el método Open.
Nota: No todos los proveedores admiten todos los métodos o propiedades del objeto Recordset.
Propiedades
Property | Description |
---|---|
AbsolutePage | Sets or returns a value that specifies the page number in the Recordset object |
AbsolutePosition | Sets or returns a value that specifies the ordinal position of the current record in the Recordset object |
ActiveCommand | Returns the Command object associated with the Recordset |
ActiveConnection | Sets or returns a definition for a connection if the connection is closed, or the current Connection object if the connection is open |
BOF | Returns true if the current record position is before the first record, otherwise false |
Bookmark | Sets or returns a bookmark. The bookmark saves the position of the current record |
CacheSize | Sets or returns the number of records that can be cached |
CursorLocation | Sets or returns the location of the cursor service |
CursorType | Sets or returns the cursor type of a Recordset object |
DataMember | Sets or returns the name of the data member that will be retrieved from the object referenced by the DataSource property |
DataSource | Specifies an object containing data to be represented as a Recordset object |
EditMode | Returns the editing status of the current record |
EOF | Returns true if the current record position is after the last record, otherwise false |
Filter | Sets or returns a filter for the data in a Recordset object |
Index | Sets or returns the name of the current index for a Recordset object |
LockType | Sets or returns a value that specifies the type of locking when editing a record in a Recordset |
MarshalOptions | Sets or returns a value that specifies which records are to be returned to the server |
MaxRecords | Sets or returns the maximum number of records to return to a Recordset object from a query |
PageCount | Returns the number of pages with data in a Recordset object |
PageSize | Sets or returns the maximum number of records allowed on a single page of a Recordset object |
RecordCount | Returns the number of records in a Recordset object |
Sort | Sets or returns the field names in the Recordset to sort on |
Source | Sets a string value or a Command object reference, or returns a String value that indicates the data source of the Recordset object |
State | Returns a value that describes if the Recordset object is open, closed, connecting, executing or retrieving data |
Status | Returns the status of the current record with regard to batch updates or other bulk operations |
StayInSync | Sets or returns whether the reference to the child records will change when the parent record position changes |
Métodos
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 |
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 |
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 |
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 |
Eventos
Nota: No puede manejar eventos usando VBScript o JScript (solo los lenguajes Visual Basic, Visual C++ y Visual J++ pueden manejar eventos).
Event | Description |
---|---|
EndOfRecordset | Triggered when you try to move to a record after the last record |
FetchComplete | Triggered after all records in an asynchronous operation have been fetched |
FetchProgress | Triggered periodically in an asynchronous operation, to state how many more records that have been fetched |
FieldChangeComplete | Triggered after the value of a Field object change |
MoveComplete | Triggered after the current position in the Recordset has changed |
RecordChangeComplete | Triggered after a record has changed |
RecordsetChangeComplete | Triggered after the Recordset has changed |
WillChangeField | Triggered before the value of a Field object change |
WillChangeRecord | Triggered before a record change |
WillChangeRecordset | Triggered before a Recordset change |
WillMove | Triggered before the current position in the Recordset changes |
Colecciones
Collection | Description |
---|---|
Fields | Indicates the number of Field objects in the Recordset object |
Properties | Contains all the Property objects in the Recordset object |
Las propiedades de la colección Fields
Property | Description |
---|---|
Count | Returns the number of items in the fields collection. Starts at zero.
Example: countfields=rs.Fields.Count |
Item(named_item/number) | Returns a specified item in the fields collection.
Example: itemfields=rs.Fields.Item(1) |
Propiedades de la colección de propiedades
Property | Description |
---|---|
Count | Returns the number of items in the properties collection. Starts at zero.
Example: countprop=rs.Properties.Count |
Item(named_item/number) | Returns a specified item in the properties collection.
Example: itemprop = rs.Properties.Item(1) |