JDBC & Servlet

[Vikram Deshmukh]

Dear friends ,
i'm using JDBC connectivity in the HttpServlet . Here is my query for
executeQuery as a parameter invoked by statement object,
Select Promotion_Date from Promotion where Emp_Code = a4
but after this statement i get error message as given below,
ERROR:
[Microsoft][ODBC Microsoft Access Driver] Too few parameters. Expected 1.
can anybody help me out ? Thanx in advance !
from ,
vikram .

[Milind Kulkarni]

Hi Vikram,
Please post the code where you are experiencing this problem.
Regards,
Milind

[Vikram Deshmukh]

Here is a code to ease the Qn.
all req imports
public class Selection extends HttpServlet
{
Connection con;
Statement stmt;
public void init(ServletConfig config) throws ServletException
{
super.init(config);
// initializing database drivers
String driverName,url,user,password;
Driver driver;
try
{
driverName = "sun.jdbc.odbc.JdbcOdbcDriver";//using JdbcOdbc bridge
driver = (Driver)Class.forName(driverName).newInstance();// registering driver
url = "jdbc dbc:Promo"; // Data Source Name
user = "";
password = "";
con = DriverManager.getConnection(url,user,password);
stmt = con.createStatement();
}
catch(Exception e)
{
e.printStackTrace();
}
}
public void doGet(HttpServletRequest req,HttpServletResponse res)
throws IOException, ServletException
{
String chbxeCode = new String();
String chbxproDate = new String();
String chbxproPost = new String();
String query = new String();
String str = null;
boolean flag = false;
String eCode = null;
String ePromoDate = null;
String ePromoPost = null;
Object obj = null;
PrintWriter pw = null;
res.setContentType("text/html");
pw = res.getWriter();
query = "Select ";
str = req.getParameter("Field_Names"); // GETTING FIELD NAMES
query = query + str + " from Promotion";
chbxeCode = chbxeCode+ req.getParameter("eCode"); // GETTING STATUS OF CHECKBOX
chbxproDate = chbxproDate + req.getParameter("proDate");
chbxproPost = chbxproPost + req.getParameter("proPost");
// NOW QUERY FORMED HERE IN BETWEEN
// ACCORDING TO CHECKBOX
pw.println(query);// this prints query as just to verify if properly constructed , & IT SHOWS XPECTED QUERY
// NOW MANAGEMENT OF DATABASE
try
{
ResultSet rs = stmt.executeQuery(query); // here is a problem
pw.println("Yes i came inside try !");// IT DOESNT PRINT THIS STATEMENT
ResultSetMetaData rsmd = rs.getMetaData();
int numcols = rsmd.getColumnCount();
// TITLE THE TABLE WITH RESULT SET'S COLUMN LABELS
// ..........code
}
catch(SQLException e)
{

}
}

public void destroy()
{
try
{
stmt.close();
con = null;
}
catch(SQLException e)
{
}
}
}
[This message has been edited by Vikram Deshmukh (edited July 10, 2000).]

[Vijaya Krishna]

Try giving the emp_name in single quotes . try the query in access and find whether it works. try appending single quotes .

Originally posted by Vikram Deshmukh:
Here is a code to ease the Qn.
all req imports
public class Selection extends HttpServlet
{
Connection con;
Statement stmt;
public void init(ServletConfig config) throws ServletException
{
super.init(config);
// initializing database drivers
String driverName,url,user,password;
Driver driver;
try
{
driverName = "sun.jdbc.odbc.JdbcOdbcDriver";//using JdbcOdbc bridge
driver = (Driver)Class.forName(driverName).newInstance();// registering driver
url = "jdbc dbc:Promo"; // Data Source Name
user = "";
password = "";
con = DriverManager.getConnection(url,user,password);
stmt = con.createStatement();
}
catch(Exception e)
{
e.printStackTrace();
}
}
public void doGet(HttpServletRequest req,HttpServletResponse res)
throws IOException, ServletException
{
String chbxeCode = new String();
String chbxproDate = new String();
String chbxproPost = new String();
String query = new String();
String str = null;
boolean flag = false;
String eCode = null;
String ePromoDate = null;
String ePromoPost = null;
Object obj = null;
PrintWriter pw = null;
res.setContentType("text/html");
pw = res.getWriter();
query = "Select ";
str = req.getParameter("Field_Names"); // GETTING FIELD NAMES
query = query + str + " from Promotion";
chbxeCode = chbxeCode+ req.getParameter("eCode"); // GETTING STATUS OF CHECKBOX
chbxproDate = chbxproDate + req.getParameter("proDate");
chbxproPost = chbxproPost + req.getParameter("proPost");
// NOW QUERY FORMED HERE IN BETWEEN
// ACCORDING TO CHECKBOX
pw.println(query);// this prints query as just to verify if properly constructed , & IT SHOWS XPECTED QUERY
// NOW MANAGEMENT OF DATABASE
try
{
ResultSet rs = stmt.executeQuery(query); // here is a problem
pw.println("Yes i came inside try !");// IT DOESNT PRINT THIS STATEMENT
ResultSetMetaData rsmd = rs.getMetaData();
int numcols = rsmd.getColumnCount();
// TITLE THE TABLE WITH RESULT SET'S COLUMN LABELS
// ..........code
}
catch(SQLException e)
{

}
}

public void destroy()
{
try
{
stmt.close();
con = null;
}
catch(SQLException e)
{
}
}
}
[This message has been edited by Vikram Deshmukh (edited July 10, 2000).]

[Vikram Deshmukh]

Thanx it worked . My new query i'm posting after this .