EVL – ETL Tool


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Table of Contents

Common Options

Mostly this invocation schema is applied on all components.

<Component>  F_IN... F_OUT... EVD_IN... EVD_OUT... EVM
        [ -v|--validate ]
        [ -x|--text-input ]
        [ -y|--text-output ]

where <Component> is the name of the component, like Read or Join.

F_IN... F_OUT...

are names of the input flows or files and of the output flows or files.

  • Flow names must be unique in each evs file. Convention is to have these names in CAPITAL LETTERS.
  • Files – if F_IN or F_OUT contains ‘/’ (foreslash), then it is treated as a file, not a flow. Remember that one can use special files, like /dev/stderr or /dev/null or in general /dev/fd/N.
EVD_IN... EVD_OUT...

specifies the evd with the information about data structure, i.e. field names, data types, nullability, separator, etc. It can be:

  • EVD file – a file with the data structure definition;
  • Inline EVD – evd can be specified inline by options this way:
    -D | --input-definition

    for input evd (when both – input and output – evd have to be specified);

    -d | --output-definition

    for output evd (when both – input and output – evd have to be specified);

    -d | --data-definition

    for input evd (whenonly one evd is needed by <Component>).

EVM

specifies the evm file which contains the mapping of the component.

All options are interpreted as in shell, so must be specified in one line or separated by ‘\’ at the end of the line.