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Metadata Structure of Stream

This is a step to read the metadata of the incoming stream.

Metadata Structure

Option

Definition

Step Name

The name of the step

Output Row

Do you want to output the rows (Y/N)

Field for Row

If "output row" is selected, name the field that will contain the output row data

Outputs

Field Name

Contents

Position

The position of the field in the inbound data stream

Fieldname

The field name in the inbound data stream

Comments

 

Type

String, Integer, Number etc

Length

The field length

Precision

Applicable for Integer, Number and -1 if not applicable (e.g. Strings)

Origin

The step where the meta data was derived from

Example

You can create an input step from a database of your choice and then create an input hop to this step.

You may choose to create inputs from two different databases which *should* have the same structure and use a "Merge rows (diff)" step to compare the structure.  If doing this, note that the case of field names are sometimes different and that the data types are also detected differently from different database engines. In this instance, I use a modified javascript to perform a "lower" on the "Fieldname" before comparing this to the other stream in the "Merge rows (diff)". It may help to sort the result by "position" to help identify where a column mismatch causes a "new" and "deleted" record.

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