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====== How to generate data with an entity? ======


===== About ====
This howto will show you how to generate data with an [[:docs:generator:entity|entity generator]].



===== Example =====



==== Basic ====

Example of a basic entity [[:docs:resource:generator|generator resource]] that uses the `firstname` entity to fill a `firstname` column
<unit>
<file yaml generator/entity-basic--generator.yml>
kind: generator
spec:
  MaxRecordCount: 10
  Columns:
    - name: firstname
      Type: varchar
      data-supplier:
        type: entity


</file>
  * You can see the output with [[:docs:tabul:data:print|tabul print]]
<code bash>
tabul data print generator/entity-basic--generator.yml@howto
</code>
<console>
firstname
---------
Cassandra
Dodie
Marcelo
Vicente
Elenora
Albert
Dimple
Dollie
Johnie
Lenna
</console>
</unit>

==== Meta Column Dependency ====

A `firstname` depends on the `gender`. Each entity may have one or more meta columns such as `gender`.

To express this dependency, you can use the ''meta_columns'' attribute to map:
  * a local column (ie from the generator)
  * to a entity column (ie from the data set)

<unit>
<file yaml generator/entity-meta-columns--generator.yml>
kind: generator
spec:
  MaxRecordCount: 30
  Columns:
    - name: gender
      Type: Varchar
      data-supplier:
        type: histogram
        arguments:
          Buckets:
            M: 1.0
            F: 2.0
    - name: firstname
      Type: Varchar
      data-supplier:
        type: entity
        arguments:
          name: firstname
          locale: en
          metaColumns:
            gender: gender


</file>
  * You can see the output with [[:docs:tabul:data:print|tabul print]]
<code bash>
tabul data print generator/entity-meta-columns--generator.yml@howto
</code>
<console height="300px" scroll="toggle">
gender   firstname
------   ---------
M        Boris
F        Britta
M        Boris
F        Ashley
F        Althea
M        Amal
F        Britt
F        Beatris
F        Betty
F        Alverta
F        Ashley
F        Bonnie
F        Barbra
F        Brittani
F        Amanda
M        Alphonso
F        Alyce
F        Alverta
F        Britta
M        Amal
F        Alysa
M        Amado
M        Arnold
F        Barbara
F        Beckie
F        Becky
F        Bonnie
M        Arnoldo
F        Amanda
F        Ashley
</console>
</unit>