最近几年来，地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持，如城市管理、区划、环境整治等等，地理信息成为信息时代重要的组成部分之一； “数字地球”概念的提出，更进一步推动了作为其技术支撑的GIS的发展。 与此同时，一些学者致力于相关的理论研究，如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面，并且这两个方面构成了相互促进的发展过程。
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. 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>