HOw to create arrays in datastage basic routines

[mahi_mahi]

Hi All,
I would like use array concept in basic routine for my requirement.

in basic routine i need to open a file and read record by record and based
on condition i need to build an array

i tried with using metaread but i could not scucceed please let me know
the correct command to use to build an array in routine by reading a file

Mahi

[ArndW]

You have 2 types of arrays in DataStage BASIC - static and dynamic. The static arrays are one or two dimensions and declared as DIM MyArray({Ycols},{Ycols}). The other type are dynamic arrays and they are not limited in either total length or number of dimensions by DS.
Dynamic arrays are very powerful but a bit tricky to get an understanding of, since they are in effect just long strings with delimiters. The builtin delimiters such as @FM, @VM, @SM, @TM (field, value, subvalue and text marks) are not the only ones that can be used. The DS/Basic manual details how these dynamic arrays can be worked with in some detail.

[kcbland]

The fastest way to read a file into an array is like this:

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UNIXcmd="cat /here/there/yourfile"
Call Execute("UNIX", UNIXcmd, ScreenOutput, ReturnCode)

The screen output of the command is return in a dynamic array variable called ScreenOutput.

To get the number of lines in the dynamic array, count them:

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LineCount=DCOUNT(ScreenOutput, @AM)

To loop thru the lines, use dynamic notation:

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For i=1 to LineCount
   Line = ScreenOutput<i>
   ...
   ...
   ...
Next i

To dynamically build an array, use the <-1> appending logic:

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Arr=""
Arr<-1>="line1"
Arr<-1>="line2"
Arr<-1>="line3"
Arr<-1>="line4"

To dynamically build a 2-D array, use @VM to separate values:

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Arr=""
Arr<-1>="line1":@VM:"multivalue1"
Arr<-1>="line2":@VM:"multivalue2"
Arr<-1>="line3":@VM:"multivalue3"
Arr<-1>="line4":@VM:"multivalue4"

To count the values in an array element (called an attribute):

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VMCount=DCOUNT(Arr<3>, @VM)

To loop thru the values in an attribute:

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For j=1 To VMCount
   MultiValue=Arr<3,j>
   ...
   ...
   ...
Next j

[kduke]

Ken

Edit your post and change @FM to @VM.

[ArndW]

You mean the @AM to @FM in the first quote

[kcbland]

Okay, I just freehanded the junk, F and V are close together on the keyboard.