# CategoryBuild

Allows you to build a category. You must build a category after you create and train a new category, as well as every time that you retrain a category. Building a category identifies the concepts of the category training and indexes the category into the IDOL Server category index.

NOTE: This is an administrative action that can be sent only by users that belong to an authorization role that allows the `Admin` standard role, or which enables the action explicitly. See Authorization Roles Configuration Parameters.

Notes:

- If you train or retrain a category by using the CategorySetTraining action with BuildNow set to `True`, you do not have to run a `CategoryBuild` action, because the category builds immediately after training.

- If you have previously built a category as a conceptual category, you cannot use `CategoryBuild` to rebuild the category as a Simple category.

- If a category has no training, you can use `CategoryBuild` to zero the category terms and weights, and synchronize them with the training.

- When CategoryInheritance is set to `True` in the configuration file (the default is `False`), and you also set the Recurse parameter to `True` for the `CategoryBuild` action, `CategoryBuild` recursively builds its ancestors as well as its descendants.

- By default, `CategoryBuild` builds and indexes only categories that require reindexing, for example if their training or certain category properties have changed.

NOTE: If you train a category against text or directly against documents, building the category fails unless at least some of the terms in the category training text are indexed into the IDOL Server on which the category is built. (This restriction does not apply to categories trained only with Boolean expressions.)

## Example

    http://12.3.4.56:9020/action=CategoryBuild&Category=32349987602210557106

This action builds the category with the ID `32349987602210557106`.

## Required Parameters

The following action parameters are required.

Parameter | Description
--- | ---
Category | The ID of the category to build.

## Optional Parameters

This action accepts the following optional parameters.

Parameter | Description
--- | ---
ForceRefresh | Whether to force categories to build and reindex.
Recurse | Whether to build the children of the category.
Relevance | Whether to build the category with the alternative `Relevance` algorithm.
Simple | Whether to use an alternative categorization algorithm.
UserName | The name of the user that sends the action.
WeightingAlgorithm | The algorithm to use to build the category.

This action accepts the following standard ACI action parameters.

Parameter | Description
--- | ---
ActionID | A string to use to identify an ACI action.
EncryptResponse | Encrypt the output.
FileName | The file to write output to.
ForceTemplateRefresh | Forces the server to load the template from disk.
Output | Writes output to a file.
ResponseFormat | The format of the action output.
Template | The template to use for the action output.
TemplateParamCSVs | A list of variables to use for the specified template.

## Comments

You can use the DatabaseMatch parameter with the CategorySetDetails action to control the generation of category terms.

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