Content deleted Content added
Successor to RDO and DAO. |
+simple examples using recordset object, compare to arbitrary sql, |
||
Line 1:
Microsoft '''ADO''' (ActiveX Data Objects) is an [[COM]] object for accessing data sources. It provides a layer between programming languages and databases, which allows a developer to write programs which access data, without knowing how the database is implemented. No knowledge of [[SQL]] is required to access a database when using ADO, although one can use ADO to execute arbritrary SQL commands. The disadvantage of this is that this introduces a dependency upon the database.
It is positioned as a successor to Microsoft's earlier object layers for accessing data sources, including [[RDO]] (Remote Data Objects) and [[DAO]] (Data Access Objects).▼
ADO consists of several top-level objects:
Line 12 ⟶ 14:
:Parameter (represents a SQL parameter)
:Property (stores information about objects)
ADO is used in conjunction with a high-level language, such as [[VBScript programming language|VBScript]] in an [[ASP]] environment. Here is an ASP example using ADO to select the "Name" field, from a table called "Phonebook", where a "PhoneNumber" was equal to "555-5555".
dim myconnection, myrecordset, name
set myconnection = server.createobject("ADODB.Connection")
set myrecordset = server.createobject("ADODB.Recordset")
myconnection.open mydatasource
myrecordset.open "Phonebook", myconnection
myrecordset.find "PhoneNumber = '555-5555'"
name = myrecordset.fields.item("Name")
myrecordset.close
set myrecordset = nothing
set myconnection = nothing
This is equivalent to the following ASP code, which uses plain SQL, instead of the functionality of the Recordset object:
dim myconnection, myrecordset, name
set myconnection = server.createobject("ADODB.connection")
myconnection.open mydatasource
set myrecordset = myconnection.execute("SELECT Name FROM Phonebook WHERE PhoneNumber = '555-5555'")
name = myrecordset(0)
myrecordset.close
set myrecordset = nothing
set myconnection = nothing
▲It is positioned as a successor to Microsoft's earlier object layers for accessing data sources, including [[RDO]] (Remote Data Objects) and [[DAO]] (Data Access Objects).
| |||