---
title: "categorical-filter"
slug: "categorical-filter-parser"
updated: 2022-07-27T23:33:15Z
published: 2022-07-27T23:33:15Z
canonical: "code.tag.bio/categorical-filter-parser"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://code.tag.bio/llms.txt
> Use this file to discover all available pages before exploring further.

# categorical-filter

The `categorical-filter` **parser** will load data from a column in a source data table and filter out some of the values before producing categorical **variables** within a **collection**.

```
{
  "parser_type": "categorical-filter",
  "table_alias": "tata",
  "column": "cccc",
  "operator": "=",
  "value": "vvvv",
  "collection": "collection_name"
}
```

## operator

**usage: *required*** The operator attribute defines a comparison function.

Options include:

= - equals
!= - not equals
_= - lowercase equals
_!= - lowercase not equals
contains - column value contains
!contains - column value does not contain
_contains - lowercase contains
_!contains - lowercase not contains
is null - column value is null
not null - column value is not null
  

## value

**usage: *required* except for *is null* or *not null*** The `value` attribute defines a constant value against which the parser will evaluate dynamic values from the column.