Talend Scenario Based Questions: Types of connections inTalend

type of connection
row	Main, Lookup, Reject, Output, Uniques/Duplicates, or Combine,filter
iterate	iterate
trigger	subJob triggers: On Subjob Ok, On Subjob Error and Run if
	component triggers: On Component Ok, On Component Error and Run if.

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type of connection description

Main This type of row connection is the most commonly used connection. It passes on data flows from one component to the other, iterating on each row and reading input data according to the component properties setting (schema)

Lookup This row connection connects a sub-flow component to a main flow component (which should be allowed to receive more than one incoming flow). This connection is used only in the case of multiple input flows.

Reject This row connection connects a processing component to an output component. This row connection gathers the data that does NOT match the filter or are not valid for the expected output. This connection allows you to track the data that could not be processed for any reason (wrong type, undefined null value, etc.). On some components, this connection is enabled when the Die on error option is deactivated.

Error reject This row connection connects a tMap component to an output component. This connection is enabled when you clear the Die on error check box in the tMap editor and it gathers data that could not be processed (wrong type, undefined null value, unparseable dates, etc.).

Filter This row connection connects specifically a tFilterRow component to an output component. This row connection gathers the data matching the filtering criteria. This particular component offers also a Reject connection to fetch the non-matching data flow.

output This row connection connects a tMap component to one or several output components. As the Job output can be multiple, you get prompted to give a name for each output row created.

Uniques The Uniques connection gathers the rows that are found first in the incoming flow. This flow of unique data is directed to the relevant output component or else to another processing subJob.

Duplicates The Duplicates connection gathers the possible duplicates of the first encountered rows. This reject flow is directed to the relevant output component, for analysis for example.

Combine This type of row connection connects one CombinedSQL component to another.

type of connection	description
Main	This type of row connection is the most commonly used connection. It passes on data flows from one component to the other, iterating on each row and reading input data according to the component properties setting (schema)
Lookup	This row connection connects a sub-flow component to a main flow component (which should be allowed to receive more than one incoming flow). This connection is used only in the case of multiple input flows.
Reject	This row connection connects a processing component to an output component. This row connection gathers the data that does NOT match the filter or are not valid for the expected output. This connection allows you to track the data that could not be processed for any reason (wrong type, undefined null value, etc.). On some components, this connection is enabled when the Die on error option is deactivated.
Error reject	This row connection connects a tMap component to an output component. This connection is enabled when you clear the Die on error check box in the tMap editor and it gathers data that could not be processed (wrong type, undefined null value, unparseable dates, etc.).
Filter	This row connection connects specifically a tFilterRow component to an output component. This row connection gathers the data matching the filtering criteria. This particular component offers also a Reject connection to fetch the non-matching data flow.
output	This row connection connects a tMap component to one or several output components. As the Job output can be multiple, you get prompted to give a name for each output row created.
Uniques	The Uniques connection gathers the rows that are found first in the incoming flow. This flow of unique data is directed to the relevant output component or else to another processing subJob.
Duplicates	The Duplicates connection gathers the possible duplicates of the first encountered rows. This reject flow is directed to the relevant output component, for analysis for example.
Combine	This type of row connection connects one CombinedSQL component to another.