Question on Custom Build Stage

[derekchu]

Hi,

I am writing a custom build stage which read a reference input into memory.

I wrote the following in the "Definition Tab"
#include <apt_util/date.h>
APT_Date Lower_Bound [500];
APT_Date Upper_Bound [500];
APT_String Value [500];
int NumLabels=0;
and I wrote the following in the "Pre-Loop" to read all records from the reference stream to memory:

readRecord(1);
while (!inputDone(1))
{
if (NumLabels <= 499)
{
Lower_Bound[NumLabels] = RefRec.Min;
Upper_Bound[NumLabels] = RefRec.Max;
Value[NumLabels] = RefRec.Value;
NumLabels++;
}
readRecord(1);
}


However as the size of the arrays are fixed (e.g. 500), I cannot read a reference stream with all records. Is there any way to due to dynamic array in custom build stage?

Regards,
Derek

[Sainath.Srinivasan]

You can very much add locations by obtaining from new.

[derekchu]

Can you elaborate more on this?

Thanks.

Regards,
Derek

[Sainath.Srinivasan]

There are many ways to allocate more locations to your variables.

One method is malloc(). Another is new.

Alternatively you can work in stacks and linked lists or create your own structure.

If it is from a file, you can use file pointers to access locations without loading into memory.

[mavrick21]

Sainath/Derek,

I'm a beginner to Custom Build Stage and I'm interested to learn more about it. Can you please tell me how do I go about it?

Thanks for your time.

[derekchu]

Sainath,

Yes, I managed with the malloc for declaring a dynamic array, and realloc when growing the array.

However I hit another problem.

If the Input field is a "null", then if I simply assign this to the variable, Datastage fails to run:

APT_String x;

x=InRec.Field1;
// where InRec is the input and Field1 contains "null"


How can we handle null value for the input?

Regards,
Derek CHU