Compare, Extract & only save delta

[#1]

Hello community,

I export a list of paths that contain IDs (which are associated to tif files) to a csv.

IDs look like this: ID00022123 or ID00022124

The path looks like this: \\server\D$\public\ID00022123.tif

I build this path with the static server string concatenated with the ID I get from a column plus the string '.tif'.

So the most recent ID is always the highest number when you take those five digits from the right.

In the DB IDs are only added not removed.

Now I want to extract the delta from a previous load. Meaning I only want to export the newly added IDs, overwriting the old entries. 

How can I make this work?

[swuehl]

Somethinge like this should work:

Old:

LOAD ID FROM ID.qvd (qvd);

New:

NOCONCATENATE

LOAD ID FROM SourceTable WHERE not EXISTS(ID);

STORE New into ID.qvd (qvd);

[#3]

What am I doing wrong?

OLD:
//LOAD ID INLINE [
//    ID
//  ID00033123
//  ID00033124
//  ID00033125
//];
//store [OLD] into ID.qvd (qvd);
LOAD ID FROM ID.qvd (qvd);

NoConcatenate
Main:
LOAD * INLINE [
    ID
  ID00033123
  ID00033124
  ID00033125
  ID00066120
];

NEW:
NoConcatenate
LOAD ID Resident Main WHERE NOT EXISTS(ID);

store NEW into ID.qvd (qvd);

[swuehl · Accepted solution]

After your Main table INLINE LOAD, all ID values already exist in the QV data model, so your NEW table load probably results in an empty table, right?

Either load the NEW values directly from an external  data source, skipping the RESIDENT LOAD, or using it like

NEW: 

NoConcatenate 

LOAD ID INLINE [ 

ID 

ID00033123 

  ID00033124 

  ID00033125 

  ID00066120 

]; 

WHERE NOT EXISTS(ID); 

or using a different field name for MAIN's ID (ID as MAINID) and use exists() with two arguments: ...WHERE NOT EXISTS(ID, MAINID)

[jagan]

Hi,

Load Main table from Excel/CSV or from database instead of Inline.  It will work.

OLD:  
LOAD ID FROM ID.qvd (qvd);    

NEW:  
NoConcatenate  
LOAD ID
FROM MaindataFileName
WHERE NOT EXISTS(ID);   

store NEW into ID.qvd (qvd);

Regards,

Jagan.

[#6]

I didn't know about the "qvd/csv trick". Now I finally got it working.

Thank you both.