> Dear Alan,
> Was the problem due to not padding the data before inserting into the
> dump file(D:\TEMP\dump.txt) ?
> Remember my dump file size was 3 GB.
> I have not casted while inserting into table i have just removed null
> chars. i.e. '\0'
> I successfully attached that dump file as EXTERNAL TABLE i.e. TEMP1
> but when i executed command this:

successful attachement does not mean anyting mush other than the file
exists. No other checking is done until you start reading it.

>
> INSERT INTO REALTABLE SELECT COL1,COL2 FROM TEMP1
>
> then it started inserting data into database but after inserting for 5
> minutes it says:
> I/O error for file fseek "D:\TEMP\dump.txt" Error while trying to open
> file.
> I have no idea why the error is coming...
>
> Please help me

hmm, I have to say it again. I get the impression that you are creating a
variable field length file. IT MUST BE A FIXED FIELD LENGTH FILE. All the
columns must be identical in length (not between but within) and all rows
must terminate with a carriage return which is correct for your Operating
System.
Show us 2 sample lines of this dump file.
Alan