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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")

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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

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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")

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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

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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

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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")

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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

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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

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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")

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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

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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")

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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:

• Immediate updating - all changes are written immediately to the database once you call the Update method.
• Batch updating - the provider cache multiple changes and then send them to the database with the UpdateBatch method.

In ADO there are 4 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.

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.

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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")

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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:

• From a URL pointing to a document, a folder, or a Record object
• By instantiating a Stream object to store data for your application
• By opening the default Stream object associated with a Record object

Syntax

objectname.property objectname.method

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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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