We can use SQL’s We want to delete If the user clicks the button in the “customerID” column, the new file “demo_delete.asp” opens.
In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress. DELETE command to delete a record in the database table.Delete records from the table ¶
Northwind database Customers a record in the table. First we need to create a table to list Customers all records.<html>
<body>
<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"
set rs=Server.CreateObject("ADODB.Recordset")
rs.open "SELECT \* FROM customers",conn
%>
<h2>List Databaseh2>
<table border="1" width="100%">
<tr>
<%
for each x in rs.Fields
response.write("
" & ucase(x.name) & "")
next
%>
tr>
<% do until rs.EOF %>
<tr>
<form method="post" action="demo_delete.html">
<%
for each x in rs.Fields
if x.name="customerID" then%>
<td>
<input type="submit" name="customerID" value="<%=x.value%>">
td>
<%else%>
<td><%Response.Write(x.value)%>td>
<%end if
next
%>
form>
<%rs.MoveNext%>
tr>
<%
loop
conn.close
%>
table>
body>
html>
<html>
<body>
<h2>Delete Recordh2>
<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"
cid=Request.Form("customerID")
if Request.form("companyname")="" then
set rs=Server.CreateObject("ADODB.Recordset")
rs.open "SELECT \* FROM customers WHERE customerID='" & cid & "'",conn
%>
<form method="post" action="demo_delete.html">
<table>
<%for each x in rs.Fields%>
<tr>
<td><%=x.name%>td>
<td><input name="<%=x.name%>" value="<%=x.value%>">td>
<%next%>
tr>
table>
<br><br>
<input type="submit" value="Delete record">
form>
<%
else
sql="DELETE FROM customers"
sql=sql & " WHERE customerID='" & cid & "'"
on error resume next
conn.Execute sql
if err<>0 then
response.write("No update permissions!")
else
response.write("Record " & cid & " was deleted!")
end if
end if
conn.close
%>
body>
html>
Principles, Technologies, and Methods of Geographic Information Systems
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