Updating a QVD

[Anonymous]

I am looking for a post to refer on updating a QVD.  I see posts with the store command.  Would I use the same command for updating the values within the QVD?  I am trying to figure out a incremental load where if it sees the same key number, there is a column that increments up.  I have a datasource that I am reading every 15 minutes. Desired outcome is if it sees the same key number it updates the count by 1, if not on the QVD, write the row out with all other applicable values tied to its row.  On next run it seems to blow out the qvd.

[Clever_Anjos]

You can´t change a QVD once is stored.

Every time a STORE command is issued the QVD is recreated from scratch using the data you have in memory at that time

[Anonymous · Accepted solution]

Based on what you stated,

1. you need extract everything from your datasource into a QV table, Table1 with a unique key KEY1

2. Load the all records from the previous QVD file (QVD1.qvd, with a key KEY) with where clause not exists (KEY1,KEY) into Table2
3.(concatemate Table2) Load the all records from the previous QVD (QVD1.qvd, with a key KEY) with where clause exists (KEY1,KEY) , plus update the count by 1 logic

4.Load the all records from Table1 with where clause not exists (KEY,KEY1) into Table2

5. store Table2 into QVD1.qvd;