Input Port Reading
Input port reading allows you to read file names or data from an optional input port. This feature is available in most of Readers.
To use input port mapping, connect an edge to an input port. Assign metadata to the edge. In the Reader, edit the File URL attribute.
The attribute value has the syntax
You can enter the value directly or with help of URL File Dialog.
processingType is optional and defines if the data is processed as plain data or URL addresses.
It can be
If not set explicitly,
discrete is applied by default.
Each data record field from an input port represents one particular data source.
Each data record field from an input port represents a URL to be loaded in and parsed.
All data fields from an input port are concatenated and processed as one input file. If the
nullvalue of this field is met, it is replaced by the
EOF. Following data record fields are parsed as another input file in the same way, i.e. until the
nullvalue is met. The Reader starts parsing data as soon as first bytes come by the port and process it progressively until EOF comes. For more information about writing with
streamprocessing type, see Output Port Writing.
Input Port Metadata
In input port reading, only metadata field of some particular data types can be used.
The type of the
FieldName input field can only be
Processing of Input Port Record
When graph runs, data is read from original data source (according to metadata of an edge connected to an optional input port of Readers) and received by a Reader through its optional input port. Each record is read independently of the other records. The specified field of each one is processed by the Reader according to the output metadata.
Readers with Input Port Reading
Remember that port reading can also be used by DBExecute
for receiving SQL commands.
Query URL will be as follows:
Metadata on the input port of EmailReader can have only one field.