Table of Contents

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Take the header of <file.qvd> and produce to standard output particular information, for example EVL data definition file or number of records.


  <file.qvd> --output=evd

  <file.qvd> --output=(json|xml)

  [ --table-name | --no-of-records | --fields | --tag=<xml_tag_name> ]

  ( --help | --usage | --version )



return the value of NoOfRecords tag


provide only fields’ information


return the value of TableName


return the value of <xml_tag_name>

Output Options:


return EVD data types definition


return information as JSON


return information as XML

EVD options:


use format argument for date data type


output EVD, XML or JSON in the inline format (for example to use EVD by other component with -d option)

-l, --null=<string>

to specify what string is used for NULL values in EVD

-q, --quote=<char>

to use a quote argument in EVD

-r, --record-separator=<char>

use sep="<char>" for last field

-s, --field-separator=<char>

use sep="<char>" for each field


use format for timestamp data type

Standard options:


print this help and exit


print short usage information and exit

-v, --verbose

print to stderr info/debug messages of the component


print version and exit


  1. EVD example:
    qvd_header some.qvd --output=evd --record-separator="\n" \
                        --null="" --date="%Y-%m-%d"

    will produce for example:

    id          int              null=""
    some_stamp  timestamp        null=""
    some_date   date("%Y-%m-%d") null=""
    value       string           null="" sep="\n"
  2. JSON example:
    qvd_header some.qvd --output=json --fields

    will produce for example:

          name: "REQUEST_HOUR",
          type: "timestamp",
          format: "%Y-%m-%d"


    qvd_header some.qvd --output=json

    will produce for example:

      "name": "Table1",
      "records": 3615,
          name: "REQUEST_HOUR",
          type: "timestamp",
          format: "%Y-%m-%d",
          "tags": [