---json
{
    "aliases": [
        { "path": ":docs:tabli:data:head" }
    ],
    "page_id": "ch987zzucvjgb8h97748x"
}
---
====== Tabul - Data Head Command ======


===== About =====
The ''data head'' command [[print|print]] only the ''N'' first records of a [[docs:resource:resource|data resource]].

This command is useful to print content of [[docs:resource:resource|data resource]] that have a big [[docs:resource:size|size]].

<note tip>
To print a data resource, you can also use:
  * the [[print|print command]] to print the whole content of a data resource
  * the [[tail|tail command]] to print the last content of a data resource
</note>


===== Syntax =====

<unit>
<code bash>
tabul data head -h
</code>
<console>
Tabul data head
===============

Print the first N rows of content of data resources.

By default, there is a limit of 10 on the number of rows printed



Examples
--------

 1 - Show the first 10 records of the table `sales` from the data store `sqlite`:


        tabul data head sales@sqlite


 2 - Show the first 500 rows of the table `time` from the data store `postgres`:


        tabul data head --limit 500 time@postgres


 3 - Show the first 10 lines from the file `request.log`:


        tabul data head request.log




Syntax
------


    tabul data head [options|flags] <data-selector...>


where:


  Arguments:

    <data-selector...>                                         One or more data or script selectors


  Data Definition Options:

    -a,--attribute <attributeName=value>                       Set specific data resource attributes


  Options:

    --limit <value>                                            Limit the number of rows printed (See footer)

    -t,--type <mediaType|mimeType|extensionFile>               The type of the resource

    -vc,--virtual-column <columnName=resourceAttributeName>    Add a virtual column with the value of a data resource attribute


  Selection Options:

    -wd,--with-dependencies                                    If set, the dependencies will be also selected


  Global Options:

    -ah,--app-home <path>                                      The app home directory (default to the .tabul.yml file directory)

    -vf,--conf <path>                                          The path to a configuration file

    -ee,--exec-env <name>                                      The execution environment (prod or dev)

    -h,--help                                                  Print this help

    -l,--log-level <error|warning|tip|info|fine>               Set the log level

    -ns,--not-strict                                           A minor error will not stop the process.

    -odu,--output-data-uri <outputDataUri>                     defines the output data uri for the feedback data (default: console)

    -oo,--output-operation <dataOperation>                     defines the data operations (replace, truncate) on an existing output resource before transfer.

    -oop,--output-transfer-operation <transferOperation>       defines the output transfer operation (insert, update, merge, copy). Default to `copy` for a file system and `insert` for a database.

    -pp,--passphrase <passphrase>                              A passphrase (master password) to decrypt the encrypted vault values (Env: TABUL_PASSPHRASE)

    --pipe-mode                                                Use pipe mode if you want to pipe the output in a shell. Pipe mode will not print the headers (ie column name) and will not make the control character visible

    -v,--version                                               Print version information




Footer
------


Important:
We don't recommend to increase the rows limit to a very high number.
This command loads the data into memory to calculate the data layout and
render data aligned properly.
Increasing the limit will then increase the memory footprint and may cause an out-of-memory error.
</console>
</unit>