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Error: "communication link failure"

I am working on a Delphi3 app. that connects to a SQL Server 6.5 database. I
keep getting this error message when I do certain things. I have a TDatabase
object that is connected to the database and two queries (master and detail)
that I need to open.

I first tried to connect them to the same database object, but Delphi seemed
to completely lock up. I bypassed that for the time-being by creating a
second database object.

Now Delphi seems to lock up anyway when I try to open the second query, but
if I wait long enough, I sometimes get the SQL error, "communication link
failure." Delphi also freezes up for some time when I even close the first
query! Then after a while it sometimes starts to respond, and the active
property is false.

I have tried completely un-installing and then re-installing Delphi and the
ODBC drivers, but nothing seems to work. Does anyone know something about
what's going on?

Here are the queries if it makes any difference:
Query 1 (Master)

SELECT Trans.Dept, Trans.Date,, Rec.TotalAmount Amount,
    Rec.PayMethod, Rec.PayFrom, Rec.ReferenceNumber
FROM TransactionRecord Trans, ReceiptTransaction Rec
WHERE = Rec.transactionid

ORDER BY Dept, Date

Query 2 (Detail)

SELECT RItem.Amount, Item.description, Sales.Qty, Sales.UnitPrice
FROM ReceiptItem RItem, Money, SalesItem Sales, Item
WHERE Money.transactionid = :id
AND RItem.moneyid =                 {Moneyid is key of
eceiptItem  }
AND Sales.moneyid = RItem.invoiceid      {   and
AND = Sales.itemid

Thanks a lot for your time! I'm at a loss for what to try!


Re:Error: "communication link failure"

The "communication link failure"  message may be the clue.  I would ensure
you have installed SP4 on both the server and client.  If the problem
persists, try a different SQL Server client network protocol.

Hope this helps.

Re:Error: "communication link failure"

I have received that error when attempting simple inserts on a table whose
unique index had been corrupted.  Damn hard problem to figure out, but I
found it when I took my SQL statement dropped it into a Query tool window
and found that it wouldn't work locally either.  I assume you've tried that

Good luck.

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