The thing is all of the extracted files that are inserted into the database have no duplicates, except for the one file that is generated last Nov 5, where our...

There are no joins in my expressions, there is a unique index(ID).

The vb program will split the strings and remove unnecessary values such as 0's, and converts strings to datetime.

I can't, because the vb program is automatically running to lessen the effort, meaning, it is assigned as a job that will run every Monday after the extracted text file...

I enforce the "no duplicates" via my vb program and it is working.

It's not joined, the data are directly inserted in the table from a text file via my vb...