ACC97: ASP Page Based on a Parameter Query May Not Refresh
ID: Q190529
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The information in this article applies to:
SYMPTOMS
Advanced: Requires expert coding, interoperability, and multi-user skills.
An Active Server Page (ASP) with parameters may not return the expected
results after it is run the first time.
CAUSE
You may experience this problem when the following conditions are true:
- You create a form based on a parameter query.
-and-
- You save a form, from Microsoft Access, as an ASP file.
-and-
- You run the query a second time and use different parameters.
-and-
- You run the query before the Web server's "session timeout" is over.
RESOLUTION
NOTE: This section contains information about editing ASP files, and
assumes that you are familiar with editing ASP files. Microsoft Access
Product Support professionals do not support customization of any HTML, HTX,
IDC, or ASP files.
You can correct this behavior by clearing the session object through
script. Once you know the session name, add the script below to the .html
file that prompts you for the parameter.
Determine the Session Name
- Use Notepad or another text editor to open the <filename>.asp or
<filename>alx.asp file created by Microsoft Access.
- Look for the line:
Set rs = Session("<SessionName>")
The name that appears between the quotation marks is the session name.
Edit the HTLM file
- Use Notepad or another text editor to open the <filename>.html file
created by Microsoft Access.
- Type the five lines below after the <BODY> tag.
<%
If IsObject(Session("<SessionName>")) Then
session.abandon
End if
%>
- Save the file as the same Qry<filename>.asp. Note that the file will
need to have a .asp extension instead of a .html extension.
MORE INFORMATION
A session object is created on the ASP page to prevent it from having to
requery the data every time it is run. The Web server will clear the
session object after a certain period. If this session object is not
cleared, the ASP page uses the original SQL string and recordset, even if
the parameters have changed. The script created by Microsoft Access checks
for this session object. If the session object exists, the script never
gets to the point where the parameters are set in the SQL string and the
recordset is created.
Steps to Reproduce Behavior
Create the ASP Page
-------------------
- On your Web Server, create a System DSN (using the Microsoft Access
ODBC driver) based on the Northwind sample database, Northwind.mdb,
and name the data source NWind97.
- Open the sample database Northwind.mdb.
- Create the following new query based on the Customers table:
Query: qryParamCust
----------------------------------
Type: Select Query
Field: CustomerID
Table: Customers
Criteria: Like [Enter ID] & "*"
Field: CompanyName
Table: Customers
Field: ContactName
Table: Customers
Field: Phone
Table: Customers
- Create the following new form:
Form: frmParamCust
---------------------------------
Caption: Customers
RecordSource: qryParamCust
Text box:
Name: CustomerID
ControlSource: CustomerID
Text box:
Name: CompanyName
ControlSource: CompanyName
Text box:
Name: ContactName
ControlSource: ContactName
Text box:
Name: Phone
ControlSource: Phone
- On the File menu, click Save As HTML. When the "Publish to the Web
Wizard" appears, click Next on the opening screen.
- On the "What do you want to publish?" screen, click the Forms tab,
and then click frmParamCust. Click Next.
- On the "What HTML document, if any, do you want to use as a default
template?" screen, click Next.
- On the "What default format type do you want to create?" screen, click
Dynamic ASP, and then click Next.
- On the "What are, or will be, the settings for the Internet database?"
screen, enter NWind97 in the Data Source Name box, and then click
Next.
NOTE: You will have to have an ODBC Data Source Name already created
on your web server that points to the Northwind database named
NWind97.
- On the "Where do you want to publish to?" screen, select a folder on
your Web server where you have Execute permission, for example
InetPub\Scripts or Webshare\Scripts, and then click Finish. On the
Enter Parameter dialog box, click OK. Close the query. The "Publish to
the Web" Wizard creates three files, frmParamCust_1.asp,
frmParamCust_1alx.asp, and frmParamCust_1.HTML.
- Use Notepad or another text editor to open the frmParamCust_1.asp
file. You need to change the SQL statement so that it will use the
appropriate sequence of parameter and wildcard characters. Change
the SQL statement so that it looks as follows:
sql = "SELECT Customers.CustomerID, Customers.CompanyName,
Customers.ContactName, Customers.Phone FROM Customers WHERE
(((Customers.CustomerID) Like '" & Request.QueryString
("[Enter ID]") & "%'))"
Save the changes and close the file.
For more information about using wildcards in an ASP page, please see the
following article in the Microsoft Knowledge Base:
ARTICLE-ID: Q162977 ACC97: ASP Query Cannot Be Used with the LIKE Predicate
Test the ASP Page
-----------------
- Start Microsoft Internet Explorer or another Web browser program.
Type the Uniform Resource Locator (URL) in the address box of your Web
browser to view frmParamCust_1.HTML. For example, if you saved your IDC
files in a folder called Test in the wwwroot folder of your Web
Server, type:
http://<servername>/test/frmParamCust_1.HTML
Note that the URL depends upon where your files are located on the Web
server.
- Type S, and then click Run Query.
Note that only customers whose CustomerID begins with the
letter S will show in the form.
- Type the same URL you entered in step 1.
- Type B, and then click Run Query.
Note that only customers whose CustomerID begins with the
letter S will show in the form.
Additional query words:
prb
Keywords : kbdta IntAsp
Version : WINDOWS:97
Platform : WINDOWS
Issue type : kbprb
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