Asp Command Object

 

Command Object Methods Command Object Properties

The Asp Command object

is used for executing process against Data store.These can be Commands that

is used to query a database and return records in a Recordset object, to execute

a bulk operation, or to manipulate the structure of a database.

To create a command

object use following syntax:

<%

Set objCommand = Server.CreateObject(“ADODB.Command”) %>

To

open a connection with data store set the ActiveConnection property to a valid

connection string. If you attempt to call the Execute method on a Command object

before setting this property to an open Connection object or valid connection

string, an error occurs.

<%

ObjCommand.ActiveConnection = ConnectionString %>

To

run the command use following syntax:

<%

ObjCommand.Execute RecordsAffected,Parameters,Options %>

All

arguments are optional.RecordsAffected is the number of records affected by

the query,Parameters allows you to write generic commands and pass in only the

information that changes,option is the type of command being run.

There

exists commands that return recordsets and that do not return any value.There

is nothing in the execute method specifies the command to run.The CommandText

property is used to set or return a relative URL that specifies a resource,

such as a file or directory. This could be  an SQL statement, a table name,

a relative URL, or a stored procedure call.If the CommandText property specifies

a row-returning query, any results that the execution generates are stored in

a new Recordset object.

<%

objCommand.CommandText=”Person”

Set objRecordset = objCommand.Execute( ,

, adCmdTable )

%>

In

the above example the CommandText is a table name.There is another way to specify

the type of command with the CommandType property prior to execution to optimize

performance.This could be adCmdText, adCmdTable , adCmdStoredProcedure.If the

CommandType property value equals adCmdUnknown (the default value), you may

experience diminished performance because ADO must make calls to the provider

to determine if the CommandText property is an SQL statement, a stored procedure,

or a table name.If the CommandType property does not match the type of command

in the CommandText property, an error occurs when you call the Execute method.

<%

Set objCommand = Server.CreateObject(“ADODB.Command”)

 ObjCommand.ActiveConnection = ConnectionString

objCommand.CommandText=”Person”

objCommand.CommandType= adCmdTable

Set objRecordset = objCommand.Execute

%>

The

above will perform the same task as open method

of recordset object. So we can open recordset as follows.

<%

Set objCommand = Server.CreateObject(“ADODB.Command”)

 ObjCommand.ActiveConnection = ConnectionString

objCommand.CommandText=”Person”

objCommand.CommandType= adCmdTable

objRecordset.Open  objCommand

%>

Top


Asp Command Object Methods

 

 

Method Description
Execute Executes

the query, SQL statement, or stored procedure specified in the CommandText

property.We have seen that in the previous session.

Cancel Cancels execution

of a pending, asynchronous method call.

Top


Properties

 

 

Property Description
ActiveConnection Indicates

to which Connection object the specified Command object currently belongs.

CommandText set or return

the text of a command represented by a Command object. This

could be  an SQL statement, a table name, a relative URL, or a stored

procedure call.

CommandType specifies

the type of command object.This could be adCmdText ,adCmdTable , adCmdStoredProcedure.If

the CommandType property value equals adCmdUnknown (the default value),

you may experience diminished performance because ADO must make calls to

the provider to determine if the CommandText property is an SQL statement,

a stored procedure, or a table name. 

CommandTimeOut Sets or returns

a Long value in seconds which indicates how long to wait for a command to

execute. Default value is 30.If you set the property to zero, ADO will wait

indefinitely until the execution is complete.

State Indicates

whether the state of the object is open or closed.The object’s State property

can have a combination of values. For example, if a statement is executing,

this property will have a combined value of adStateOpen and adStateExecuting.

Top


 

Leave a Comment