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Receive and Output H2 Database Column Value
Posted: 30 Nov 2010, 00:02
by coolboy714cp
I've been trying to do this for a few days now and I can't figure out what the command would be to get the value from an H2 database column and output it on the server inside a trace() command. From there I would be able to use the _server.sendResponse command to send it to the client.
Anyway, I've read the documentation and looked over the example files that had anything to do with databases. The closest thing I have gotten to getting the values from a column is the server tracing this:
, ,
However, I need the server to obtain and be able to trace out the correct values in the column.
Does anyone know what I would have to do to acheive this?
Posted: 30 Nov 2010, 17:46
by rjgtav
Hi. You could use:
for (var i = 0; i < queryRes.size(); i++){
var Row = queryRes.get(i)
value = Row.getItem("COLLUM NAME");
trace("value retrieved from the database: "+value);
}
Posted: 30 Nov 2010, 22:39
by coolboy714cp
Tried it about 10 times with editing the code a little on each one. None of them worked. The value always came out as null.
Posted: 01 Dec 2010, 03:28
by BigFIsh
Please show us your code used to fetch values from the database.
Posted: 02 Dec 2010, 03:45
by coolboy714cp
Hello BigFish, I just recently tested with the SmartFoxServer Server Side API example, and the code I used was this:
Code: Select all
function handleRequest(cmd, params, user, fromRoom)
{
// create a SQL statement
var sql = "SELECT * FROM contacts ORDER BY name"
// execute query on DB
// queryRes is a ResultSet object
var queryRes = dbase.executeQuery(sql)
// If the queryRes is not null the query was successfull
if (queryRes != null) {
// Cycle through all records in the ResultSet
for (var i = 0; i < queryRes.size(); i++) {
// Get a record
var tempRow = queryRes.get(i)
trace("Record n." + i)
trace("Name: " + tempRow.getItem("name"))
trace("Location: " + tempRow.getItem("location"))
trace("Email: " + tempRow.getItem("email"))
trace("-------------------------------------------")
}
}
}
The name, location, and email values all traced out as null, but the Record n. value traced out correctly.
Posted: 02 Dec 2010, 06:28
by BigFIsh
That looks fine to me.
The only explainable reason for null values is that those columns does not exist in your database. I think the column names are case sensitive.
Posted: 02 Dec 2010, 21:29
by coolboy714cp
The only explainable reason for null values is that those columns does not exist in your database. I think the column names are case sensitive.
I know that, but I don't think that could be the problem. The columns and tables appear in my H2 Database, and when I created a testing table, for the table name I used the following:
test
I then went on to create two tables which were:
id
and
name
When I edited the exdtension's coding, it looked something like this:
Code: Select all
function handleRequest(cmd, params, user, fromRoom)
{
// create a SQL statement
var sql = "SELECT * FROM test ORDER BY name"
// execute query on DB
// queryRes is a ResultSet object
var queryRes = dbase.executeQuery(sql)
// If the queryRes is not null the query was successfull
if (queryRes != null) {
// Cycle through all records in the ResultSet
for (var i = 0; i < queryRes.size(); i++) {
// Get a record
var tempRow = queryRes.get(i)
trace("Record n." + i)
trace("Name: " + tempRow.getItem("name"))
trace("Id: " + tempRow.getItem("id"))
trace("-------------------------------------------")
}
}
}
The values still traced out as null.
Posted: 03 Dec 2010, 04:26
by BigFIsh
Maybe the cell data have null values in them? Apart from that, I can't think of any other 'obvious' explanation to the problem.
Posted: 03 Dec 2010, 12:48
by rjgtav
also, you could try NAME and ID instead of name and id
Posted: 03 Dec 2010, 23:23
by coolboy714cp
I have tried name and id. And also the tables don't have any null values in them.
Posted: 04 Dec 2010, 12:24
by rjgtav
is the table name correct? Running out of clues..
Posted: 04 Dec 2010, 17:32
by coolboy714cp
Yes, the table name is correct.
Posted: 07 Dec 2010, 20:15
by coolboy714cp
So I'm guessing no one knows what the problem is for me...
Posted: 07 Dec 2010, 20:21
by BigFIsh
Yea.. I have already ran out of clues.
I suggest starting again from scratch, using the tutorials as a template.
Posted: 10 Dec 2010, 23:14
by coolboy714cp
Alright, I'll give that a go within the next couple of days.
