MetaPivot

Home \| Table of Contents	MetaPivot	CloverETL 4.7.0
Prev	Transformers	Next

Short Description

MetaPivot converts every incoming record into several output records, each one representing a single field from the input.

Component	Same input metadata	Sorted inputs	Inputs	Outputs	Java	CTL	Auto-propagated metadata
MetaPivot	-		1	1

Icon

Ports

Port type	Number	Required	Description	Metadata
Input	0		For input data records	Any1
Output	0		For transformed data records	Any2

Metadata

MetaPivot does not propagate metadata.

MetaPivot has a metadata template on it's output port.

	Important
	When working with MetaPivot, you have to use a fixed format of the output metadata. The metadata fields represent particular data types. Field names and data types have to be set exactly as follows (otherwise unexpected `BadDataFormatException` will occur):

Field Name	Type	Description
recordNo	long	the serial number of a record (outputs can be later grouped by this) - fields of the same record share the same number
fieldNo	integer	the current field number: 0...n-1 where n is the number of fields in the input metadata
fieldName	string	name of the field as it appeared on the input
fieldType	string	the field type, e.g. "string", "date", "decimal"
valueBoolean	boolean	the boolean value of the field
valueByte	byte	the byte value of the field
valueDate	date	the date value of the field
valueDecimal	decimal	the decimal value of the field
valueInteger	integer	the integer value of the field
valueLong	long	the long value of the field
valueNumber	number	the number value of the field
valueString	string	the string value of the field

MetaPivot Attributes

MetaPivot has no transformation-affecting attributes.

Details

On its single input port, MetaPivot receives data that do not have to be sorted. Each field of the input record is written as a new line on the output. The metadata represent data types and are restricted to a fixed format, see Details All in all, MetaPivot can be used to effectively transform your records to a neat data-dependent structure.

Unlike Normalizer, which MetaPivot is derived from, no transformation is defined. MetaPivot always does the same transformation: it takes the input records and "rotates them" thus turning input columns to output rows.

The total number of output records produced by MetaPivot equals to (number of input records) * (number of input fields).

You may have noticed some of the fields only make the output look better arranged. That is true - if you needed to omit them for whatever reasons, you can do it. The only three fields that do not have to be included in the output metadata are: recordNo, fieldNo and fieldType.

Examples

Converting Line to List

Convert records with metadata fields username, surname and firstname

doejohn|Doe  |John     
smithel|Smith|Elisabeth
...

into lines having each field value on a separate line:

username |doejohn
surname  |John
firstname|Doe
username |smithel
surname  |Elisabeth
firstname|Smith
...

Solution

Place the component into a graph and connect edges. There is nothing to be set up.

Note: You need Reformat to exclude unnecessary output fields.