ADO Recordsets: Creating and Manipulating Data with ADO, Slides of Fundamentals of E-Commerce

Download ADO Recordsets: Creating and Manipulating Data with ADO and more Slides Fundamentals of E-Commerce in PDF only on Docsity! The RecordSet Object • Used to return rows to the client. • #1 most used part of ADO • Can be created alone or with a connection object to "pool" connections. • Can be used to execute stored procedures without parameters. • Can be created w/o a connection object • Is created from "ADODB.Recordset" Docsity.com Using the connection object to return a recordset ' You can use a select statement to 'create' a snapshot forward only, ' read only cursor. (A "firehose" cursor) dim rs 'as ADODB.Recordset dim mySQL 'as string mySQL = "Select * from authors" Set rs = CN.Execute mySQL '... Use cursor rs.Close set rs = nothing Docsity.com Recordset Methods • .MoveFirst, .MoveLast, .MovePrevious, .MoveNext (moves cursor in rows, error if .EOF or .BOF or if .RecordCount = 0) • .Move n (moves number of rows specified by, see note above) • .AddNew (adds a new row to recordset, applies defaults if any, needs to be followed by .Update) • .Update (commits changes to .Recordset) • .UpdateBatch (use in addition to update with batch locking) Docsity.com Recordset Example #1 'Assuming rs is a ADODB.Recordset object If rs.State = adStateOpen Then If rs.RecordCount <> 0 Then rs.MoveFirst While not rs.EOF '… do something with records rs.MoveNext Wend End IF End If Docsity.com Explanations #1a • EOF and BOF are functions that return true if we are at the end or beginning of a recordset. To check to make sure we are actually on a good (usable record) we should: If not (rs.EOF or rs.BOF) Then Docsity.com