APENDICE : ACTIVEX DATA OBJECT

Fecha: 18/Mar/2005 (05/03/2005)
Autor: Arbis Percy Reyes Paredes - Perxindrome [email protected]

 


TODO EL APENDICE FUE TOMADO DE WWW.W3SCHOOLS.COM


Command Object

The ADO Command object is used to execute a single query against a database. The query can perform actions like creating, adding, retrieving, deleting or updating records.

If the query is used to retrieve data, the data will be returned as a RecordSet object. This means that the retrieved data can be manipulated by properties, collections, methods, and events of the Recordset object.

The major feature of the Command object is the ability to use stored queries and procedures with parameters.

ProgID

set objCommand=Server.CreateObject("ADODB.command")


Properties

Property

Description

ActiveConnection

Sets or returns a definition for a connection if the connection is closed, or the current Connection object if the connection is open

CommandText

Sets or returns a provider command

CommandTimeout

Sets or returns the number of seconds to wait while attempting to execute a command

CommandType

Sets or returns the type of a Command object

Name

Sets or returns the name of a Command object

Prepared

Sets or returns a Boolean value that, if set to True, indicates that the command should save a prepared version of the query before the first execution

State

Returns a value that describes if the Command object is open, closed, connecting, executing or retrieving data

Methods

Method

Description

Cancel

Cancels an execution of a method

CreateParameter

Creates a new Parameter object

Execute

Executes the query, SQL statement or procedure in the CommandText property

Collections

Collection

Description

Parameters

Contains all the Parameter objects of a Command Object

Properties

Contains all the Property objects of a Command Object


Connection Object

The ADO Connection Object is used to create an open connection to a data source. Through this connection, you can access and manipulate a database.

If you want to access a database multiple times, you should establish a connection using the Connection object. You can also make a connection to a database by passing a connection string via a Command or Recordset object. However, this type of connection is only good for one specific, single query.

ProgID

set objConnection=Server.CreateObject("ADODB.connection")


Properties

Property

Description

Attributes

Sets or returns the attributes of a Connection object

CommandTimeout

Sets or returns the number of seconds to wait while attempting to execute a command

ConnectionString

Sets or returns the details used to create a connection to a data source

ConnectionTimeout

Sets or returns the number of seconds to wait for a connection to open

CursorLocation

Sets or returns the location of the cursor service

DefaultDatabase

Sets or returns the default database name

IsolationLevel

Sets or returns the isolation level

Mode

Sets or returns the provider access permission

Provider

Sets or returns the provider name

State

Returns a value describing if the connection is open or closed

Version

Returns the ADO version number

Methods

Method

Description

BeginTrans

Begins a new transaction

Cancel

Cancels an execution

Close

Closes a connection

CommitTrans

Saves any changes and ends the current transaction

Execute

Executes a query, statement, procedure or provider specific text

Open

Opens a connection

OpenSchema

Returns schema information from the provider about the data source

RollbackTrans

Cancels any changes in the current transaction and ends the transaction

Events

Note: You cannot handle events using VBScript or JScript (only Visual Basic, Visual C++, and Visual J++ languages can handle events).

Event

Description

BeginTransComplete

Triggered after the BeginTrans operation

CommitTransComplete

Triggered after the CommitTrans operation

ConnectComplete

Triggered after a connection starts

Disconnect

Triggered after a connection ends

ExecuteComplete

Triggered after a command has finished executing

InfoMessage

Triggered if a warning occurs during a ConnectionEvent operation

RollbackTransComplete

Triggered after the RollbackTrans operation

WillConnect

Triggered before a connection starts

WillExecute

Triggered before a command is executed

Collections

Collection

Description

Errors

Contains all the Error objects of the Connection object

Properties

Contains all the Property objects of the Connection object


Error Object

The ADO Error object contains details about data access errors that have been generated during a single operation.

ADO generates one Error object for each error. Each Error object contains details of the specific error, and are stored in the Errors collection. To access the errors, you must refer to a specific connection.

To loop through the Errors collection:

<%
for each objErr in objConn
  response.write("<p>")
  response.write("Description: ")
  response.write(objErr.Description & "<br />")
  response.write("Help context: ")
  response.write(objErr.HelpContext & "<br />")
  response.write("Help file: ")
  response.write(objErr.HelpFile & "<br />")
  response.write("Native error: ")
  response.write(objErr.NativeError & "<br />")
  response.write("Error number: ")
  response.write(objErr.Number & "<br />")
  response.write("Error source: ")
  response.write(objErr.Source & "<br />")
  response.write("SQL state: ")
  response.write(objErr.SQLState & "<br />")
  response.write("</p>")
next
%>

Syntax

objErr.property

Properties

Property

Description

Description

Returns an error description

HelpContext

Returns the context ID of a topic in the Microsoft Windows help system

HelpFile

Returns the full path of the help file in the Microsoft Windows help system

NativeError

Returns an error code from the provider or the data source

Number

Returns a unique number that identifies the error

Source

Returns the name of the object or application that generated the error

SQLState

Returns a 5-character SQL error code


Field Object

The ADO Field object contains information about a column in a Recordset object. There is one Field object for each column in the Recordset.

ProgID

set objField=Server.CreateObject("ADODB.field")


Properties

Property

Description

ActualSize

Returns the actual length of a field's value

Attributes

Sets or returns the attributes of a Field object

DefinedSize

Returns the defined size of a field

Name

Sets or returns the name of a Field object

NumericScale

Sets or returns the number of decimal places allowed for numeric values in a Field object

OriginalValue

Returns the original value of a field

Precision

Sets or returns the maximum number of digits allowed when representing numeric values in a Field object

Status

Returns the status of a Field object

Type

Sets or returns the type of a Field object

UnderlyingValue

Returns the current value of a field

Value

Sets or returns the value of a Field object

Methods

Method

Description

AppendChunk

Appends long binary or character data to a Field object

GetChunk

Returns all or a part of the contents of a large text or binary data Field object

Collections

Collection

Description

Properties

Contains all the Property objects for a Field object


Parameter Object

The ADO Parameter object provides information about a single parameter used in a stored procedure or query.

A Parameter object is added to the Parameters Collection when it is created. The Parameters Collection is associated with a specific Command object, which uses the Collection to pass parameters in and out of stored procedures and queries.

Parameters can be used to create Parameterized Commands. These commands are (after they have been defined and stored) using parameters to alter some details of the command before it is executed. For example, an SQL SELECT statement could use a parameter to define the criteria of a WHERE clause.

There are four types of parameters: input parameters, output parameters, input/output parameters and return parameters.

Syntax

objectname.property
objectname.method

Properties

Property

Description

Attributes

Sets or returns the attributes of a Parameter object

Direction

Sets or returns how a parameter is passed to or from a procedure

Name

Sets or returns the name of a Parameter object

NumericScale

Sets or returns the number of digits stored to the right side of the decimal point for a numeric value of a Parameter object

Precision

Sets or returns the maximum number of digits allowed when representing numeric values in a Parameter

Size

Sets or returns the maximum size in bytes or characters of a value in a Parameter object

Type

Sets or returns the type of a Parameter object

Value

Sets or returns the value of a Parameter object

Methods

Method

Description

AppendChunk

Appends long binary or character data to a Parameter object

Delete

Deletes an object from the Parameters Collection


Property Object

The ADO Property object represents a dynamic characteristic of an ADO object that is defined by the provider.

Each provider that talks with ADO has different ways of interacting with ADO. Therefore, ADO needs to store information about the provider in some way. The solution is that the provider gives specific information (dynamic properties) to ADO. ADO stores each provider property in a Property object that is again stored in the Properties Collection. The Collection is assigned to either a Command object, Connection object, Field object, or a Recordset object.

ProgID

set objProperty=Server.CreateObject("ADODB.property")


Properties

Property

Description

Attributes

Returns the attributes of a Property object

Name

Sets or returns a the name of a Property object

Type

Returns the type of a Property object

Value

Sets or returns the value of a Property object


Record Object (ADO version 2.5)

The ADO Record object is used to hold a row in a Recordset, a directory, or a file from a file system.

Only structured databases could be accessed by ADO in versions prior 2.5. In a structured database, each table has the exact same number of columns in each row, and each column is composed of the same data type.

The Record object allows access to data-sets where the number of columns and/or the data type can be different from row to row.

Syntax

objectname.property
objectname.method

Properties

Property

Description

ActiveConnection

Sets or returns which Connection object a Record object belongs to

Mode

Sets or returns the permission for modifying data in a Record object

ParentURL

Returns the absolute URL of the parent Record

RecordType

Returns the type of a Record object

Source

Sets or returns the src parameter of the Open method of a Record object

State

Returns the status of a Record object

Methods

Method

Description

Cancel

Cancels an execution of a CopyRecord, DeleteRecord, MoveRecord, or Open call

Close

Closes a Record object

CopyRecord

Copies a file or directory to another location

DeleteRecord

Deletes a file or directory

GetChildren

Returns a Recordset object where each row represents the files in the directory

MoveRecord

Moves a file or a directory to another location

Open

Opens an existing Record object or creates a new file or directory

Collections

Collection

Description

Properties

A collection of provider-specific properties

Fields

Contains all the Field objects in the Record object

The Fields Collection's Properties

Property

Description

Count

Returns the number of items in the fields collection. Starts at zero.

Example:

countfields = rec.Fields.Count

Item(named_item/number)

Returns a specified item in the fields collection.

Example:

itemfields = rec.Fields.Item(1)
or
itemfields = rec.Fields.Item("Name")


Recordset Object

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 most used object to manipulate data from a database.

ProgID

set objRecordset=Server.CreateObject("ADODB.recordset")


When you first open a Recordset, the current record pointer will point to the first record and the BOF and EOF properties are False. If there are no records, the BOF and EOF property are True.

Recordset objects can support two types of updating:

In ADO there are 4 different cursor types defined:

The cursor type can be set by the CursorType property or by the CursorType parameter in the Open method.

Note: Not all providers supports all methods or properties of the Recordset object.


Properties

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 back 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

Methods

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

Events

Note: You cannot handle events using VBScript or JScript (only Visual Basic, Visual C++, and Visual J++ languages can handle events).

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

Collections

Collection

Description

Fields

Indicates the number of Field objects in the Recordset object

Properties

Contains all the Property objects in the Recordset object

The Fields Collection's Properties

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)
or
itemfields = rs.Fields.Item("Name")

The Properties Collection's Properties

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)
or
itemprop = rs.Properties.Item("Name")


Stream Object (ADO version 2.5)

The ADO Stream Object is used to read, write, and manage a stream of binary data or text.

A Stream object can be obtained in three ways:

Syntax

objectname.property
objectname.method


Properties

Property

Description

CharSet

Sets or returns a value that specifies into which character set the contents are to be translated. This property is only used with text Stream objects (type is adTypeText)

EOS

Returns whether the current position is at the end of the stream or not

LineSeparator

Sets or returns the line separator character used in a text Stream object

Mode

Sets or returns the available permissions for modifying data

Position

Sets or returns the current position (in bytes) from the beginning of a Stream object

Size

Returns the size of an open Stream object

State

Returns a value describing if the Stream object is open or closed

Type

Sets or returns the type of data in a Stream object

Methods

Method

Description

Cancel

Cancels an execution of an Open call on a Stream object

Close

Closes a Stream object

CopyTo

Copies a specified number of characters/bytes from one Stream object into another Stream object

Flush

Sends the contents of the Stream buffer to the associated underlying object

LoadFromFile

Loads the contents of a file into a Stream object

Open

Opens a Stream object

Read

Reads the entire stream or a specified number of bytes from a binary Stream object

ReadText

Reads the entire stream, a line, or a specified number of characters from a text Stream object

SaveToFile

Saves the binary contents of a Stream object to a file

SetEOS

Sets the current position to be the end of the stream (EOS)

SkipLine

Skips a line when reading a text Stream

Write

Writes binary data to a binary Stream object

WriteText

Writes character data to a text Stream object


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