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New Term:An In parameter is similar to an In argument in which the argument variable is to be used locally without modifying it. An Out parameter is an argument variable that is modified by the stored procedure. |
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As with ODBC, not all ADO vendor drivers support every feature of ADO. Microsoft keeps you abreast of what ADO features are supported at www.microsoft.com/data/ado. |
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The notable objects exposed by ADO and in common with, or similar to, DAO and RDO are the following: |
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ADODB.Connection
ADODB.Error
ADODB.Errors
ADODB.Field/ ADOR.Field
ADODB.Fields/ADOR.Fields
ADODB.Recordset/ADOR.Recordset
ADODB.Command.CommandText |
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If you've programmed database applications in Visual Basic for only a few months, you've no doubt worked with Data Access Objects (DAO). DAO is the first object library/data access mechanism that provides an interface to the Microsoft Jet database engine to access native Jet database as well as other kinds of data sources. If you used the Data control, you will recognize that its data access architecture is based on DAO. It's probably safe to say that DAO is one of the most popularly used data access mechanism available to Visual Basic developers. ODBCDirect, in fact, is derived from DAO, exposing many RDO functions. |
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Data Access Objects are mainly designed for optimum use with Microsoft Access, due to both DAO and Access supporting the Jet database engine. Among Visual Basic developers, DAO has lost ground to RDO since early 1997. |
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The Data Access Objects (version 3.5) in common with, or similar to, counterparts in ADO and RDO include |
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DAO.Connection
DAO.Connections
DAO.Database
DAO.Databases
DAO.Error
DAO.Errors
DAO.Field
DAO.Fields
DAO.QueryDef.SQL
DAO.Recordset
DAO.Recordsets |
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