topic Re: Parsing fields from a string in QlikView

Parsing fields from a string

yura_ratu — Fri, 18 Sep 2015 13:12:07 GMT

Hi Community,

I need to reconstruct a table from a string. Input is as follows.

ID	Comment
1	Field1 : [Old]ValueOld[New]ValueNew Field2 : [Old]Dummy Text Old [New]New Dummy Text New Field3 : [Old]Dummy Text Old [New]New Dummy Text New

Wanted ouput:

ID	FieldName	OldValue	NewValue
1	Field1	ValueOld	ValueNew
1	Field2	Dummy Text Old	Dummy Text New
1	Field3	Dummy Text Old	Dummy Text New

There could be any amount of Fields within a string, however their names are always without spaces

Stuck a little bit with transformations. Thanks for help!

Re: Parsing fields from a string

marcus_sommer — Fri, 18 Sep 2015 13:41:32 GMT

Is this Comment-field the definitely format for this string - then in your example is no unique delimiter for the rows? If you have one it would be quite easy to split the string per subfield(string, delimiter) which split the string on the delimiter and repeated the other parts from this record. Quite similar is to use a while-loop whereby iterno() <= substringcount(delimiter). The other string-parts for the old- and new value could be split per subfield(string, delimiter, number) or textbetween() or maybe some nested mid/left/right- and index-functions.

I think if you haven't such unique delimiter you will need to do it quite similar only that you will need additionally steps within a if-loop where the current record-value with a previous record will be per peek() or previous() compared and the record-values will be adjusted. The worser the datastructure are the more efforts do you need with this comparing, checking and adjusting.

Maybe the following links are helpful in understanding what I mean:

Re: Vertical Data Text in Pivot Table

Re: Line adding ETL

- Marcus

Re: Parsing fields from a string

MarcoWedel — Sun, 20 Sep 2015 00:43:32 GMT

Hi,

one solution could be:

table1:
Generic
LOAD ID,
    SubField(SubComment,' : [',1) as FieldName,
    TextBetween(SubComment,'[',']',IterNo())&'Value' as ColNam,
    TextBetween(SubComment&'[',']','[',IterNo()) as ColVal
While IterNo() <= SubStringCount(SubComment,'[');
LOAD ID,
    Trim(Mid(Comment, Alt(Previous(Pos)+1,1),RangeSum(Pos,-Previous(Pos)))) as SubComment;
LOAD *,
    If(IterNo()=SubStringCount(Comment,' : ['),Len(Comment),Index(Left(Comment,Index(Comment,' : [',IterNo()+1)-1),' ',-1)) as Pos
INLINE "
    ID, Comment
    1, Field1 : [Old]ValueOld[New]ValueNew Field2 : [Old]Dummy Text Old [New]New Dummy Text New Field3 : [Old]Dummy Text Old [New]New Dummy Text New
"
While IterNo() <= SubStringCount(Comment,' : [');

hope this helps

regards

Marco

Re: Parsing fields from a string

yura_ratu — Mon, 21 Sep 2015 09:16:30 GMT

Hi Marco,

Works good, thank you

Re: Parsing fields from a string

MarcoWedel — Mon, 21 Sep 2015 09:38:47 GMT

You're welcome

Regards

Marco