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inetserver asp db
group:cant get multiple random records (can get 1 ok)
inetserver asp db:
hi everyone. i have the following code that pulls a random record from an
access database: Randomize() randNum = CInt((oRS.RecordCount - 1) * Rnd) oRS.Move randNum Response.Write(oRS("FIELD1") ) this works fine. it opens a recordset, gets a count of numrecords, then moves to a random record within that count. if i put this in a loop it fails For i = 1 To 3 Randomize() randNum = CInt((oRS.RecordCount - 1) * Rnd) oRS.Move randNum Response.Write(oRS("FIELD1")) Next this might load on the first try, but a refresh usually produces the error "either eof or bof is true etc..." how is this possibly happening?
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Joe Reynolds wrote: > hi everyone. i have the following code that pulls a random record > from an access database: > > Randomize() > randNum = CInt((oRS.RecordCount - 1) * Rnd) > oRS.Move randNum > Response.Write(oRS("FIELD1") ) > > this works fine. it opens a recordset, gets a count of numrecords, > then moves to a random record within that count. > if i put this in a loop it fails > > For i = 1 To 3 > Randomize() > randNum = CInt((oRS.RecordCount - 1) * Rnd) > oRS.Move randNum > Response.Write(oRS("FIELD1")) > Next > > this might load on the first try, but a refresh usually produces the > error "either eof or bof is true etc..." > how is this possibly happening? I can't say without seeing more of the code (what cursor type are you using?). Here is a better way to get a random record. It requires the existence of an autonumber field in your table: http://www.adopenstatic.com/faq/randomrecord.asp -- Microsoft MVP -- ASP/ASP.NET Please reply to the newsgroup. The email account listed in my From header is my spam trap, so I don't check it very often. You will get a quicker response by posting to the newsgroup.
heres the page im testing with:
Dim oConn, oRS, randNum, strSQL, strDate, strComments, intCount Set oConn=Server.CreateObject("ADODB.Connection") Set oRS=Server.CreateObject("ADODB.recordset") oConn.Provider="Microsoft.Jet.OLEDB.4.0" oConn.Open Server.MapPath("comments.mdb") strSQL = "SELECT DATE_TEXT, COMMENTS_TEXT FROM TBL_COMMENTS" oRS.Open strSQL, oConn, adOpenStatic, adLockReadOnly For intCount = 1 To 2 Randomize() randNum = CInt((oRS.RecordCount - 1) * Rnd) oRS.Move randNum Response.Write("recordcount: " & oRS.RecordCount & "<br>") Response.Write("random number: " & randNum & "<br>") Response.Write(oRS("DATE_TEXT") & "<br>") Response.Write(oRS("COMMENTS_TEXT") & "<br>") Response.Write("<br>") Next oRS.close oConn.close Set oConn = nothing Set oRS = nothing [quoted text, click to view] "Bob Barrows [MVP]" <reb01501@NOyahoo.SPAMcom> wrote in message news:ezNZFJX4GHA.3452@TK2MSFTNGP05.phx.gbl... > Joe Reynolds wrote: >> hi everyone. i have the following code that pulls a random record >> from an access database: >> >> Randomize() >> randNum = CInt((oRS.RecordCount - 1) * Rnd) >> oRS.Move randNum >> Response.Write(oRS("FIELD1") ) >> >> this works fine. it opens a recordset, gets a count of numrecords, >> then moves to a random record within that count. >> if i put this in a loop it fails >> >> For i = 1 To 3 >> Randomize() >> randNum = CInt((oRS.RecordCount - 1) * Rnd) >> oRS.Move randNum >> Response.Write(oRS("FIELD1")) >> Next >> >> this might load on the first try, but a refresh usually produces the >> error "either eof or bof is true etc..." >> how is this possibly happening? > > I can't say without seeing more of the code (what cursor type are you > using?). > > Here is a better way to get a random record. It requires the existence > of an autonumber field in your table: > > http://www.adopenstatic.com/faq/randomrecord.asp > > -- > Microsoft MVP -- ASP/ASP.NET > Please reply to the newsgroup. The email account listed in my From > header is my spam trap, so I don't check it very often. You will get a > quicker response by posting to the newsgroup. > >
hey thanks.
im using that link you provided in conjunction with an AJAX function and its working great. although i would love to know why my original code wasnt working. [quoted text, click to view] "Bob Barrows [MVP]" <reb01501@NOyahoo.SPAMcom> wrote in message news:ezNZFJX4GHA.3452@TK2MSFTNGP05.phx.gbl... > Joe Reynolds wrote: >> hi everyone. i have the following code that pulls a random record >> from an access database: >> >> Randomize() >> randNum = CInt((oRS.RecordCount - 1) * Rnd) >> oRS.Move randNum >> Response.Write(oRS("FIELD1") ) >> >> this works fine. it opens a recordset, gets a count of numrecords, >> then moves to a random record within that count. >> if i put this in a loop it fails >> >> For i = 1 To 3 >> Randomize() >> randNum = CInt((oRS.RecordCount - 1) * Rnd) >> oRS.Move randNum >> Response.Write(oRS("FIELD1")) >> Next >> >> this might load on the first try, but a refresh usually produces the >> error "either eof or bof is true etc..." >> how is this possibly happening? > > I can't say without seeing more of the code (what cursor type are you > using?). > > Here is a better way to get a random record. It requires the existence > of an autonumber field in your table: > > http://www.adopenstatic.com/faq/randomrecord.asp > > -- > Microsoft MVP -- ASP/ASP.NET > Please reply to the newsgroup. The email account listed in my From > header is my spam trap, so I don't check it very often. You will get a > quicker response by posting to the newsgroup. > >
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Joe Reynolds wrote: > hey thanks. > im using that link you provided in conjunction with an AJAX function > and its working great. > although i would love to know why my original code wasnt working. > Frankly, I really don't care to spend the time to look at it. It's a grossly inefficient way to accomplish the task. -- Microsoft MVP -- ASP/ASP.NET Please reply to the newsgroup. The email account listed in my From header is my spam trap, so I don't check it very often. You will get a quicker response by posting to the newsgroup.
thank you for explaining that. it makes perfect sense.
[quoted text, click to view] "Daniel Crichton" <msnews@worldofspack.com> wrote in message news:eyABZWY4GHA.2596@TK2MSFTNGP06.phx.gbl... > Joe wrote on Tue, 26 Sep 2006 11:02:56 -0400: > >> hey thanks. >> im using that link you provided in conjunction with an AJAX function and >> its working great. >> although i would love to know why my original code wasnt working. > > The Move method doesn't move to a particular row, it moves forward that > many rows. So, here's a simple example > > rows = 10 > rand = 6 > > .Move 6 will move to row 6 > > rand = 5 > > .Move 5 will move to row 11 (as you're already on row 6), hence the error > when you read the row details (as you're now past the last row, so EOF is > true) > > You could have used the AbsolutePosition property if you didn't use the > default ForwardOnly cursor to go to a particular row (which is zero based > so you'd have to remember to subtract 1 from your random number), or use > MoveFirst between each Move method call to get back to the start (again > needing a non-ForwardOnly cursor), but it's still a poor way to pick > random rows from a recordset. > > Dan >
Joe wrote on Tue, 26 Sep 2006 11:02:56 -0400:
[quoted text, click to view] > hey thanks. > im using that link you provided in conjunction with an AJAX function and > its working great. > although i would love to know why my original code wasnt working. The Move method doesn't move to a particular row, it moves forward that many rows. So, here's a simple example rows = 10 rand = 6 ..Move 6 will move to row 6 rand = 5 ..Move 5 will move to row 11 (as you're already on row 6), hence the error when you read the row details (as you're now past the last row, so EOF is true) You could have used the AbsolutePosition property if you didn't use the default ForwardOnly cursor to go to a particular row (which is zero based so you'd have to remember to subtract 1 from your random number), or use MoveFirst between each Move method call to get back to the start (again needing a non-ForwardOnly cursor), but it's still a poor way to pick random rows from a recordset. Dan
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