ASCII folding

The asciifolding** **filter converts characters outside the Basic Latin Unicode block (the first 127 ASCII characters) into their ASCII equivalents. For instance, it transforms characters like í to i, making text processing simpler and more consistent, especially for multilingual content.

Configuration

The asciifolding filter is built into Milvus. To use it, simply specify its name in the filter section within analyzer_params.

analyzer_params = {
    "tokenizer": "standard",
    "filter": ["asciifolding"],
}

The asciifolding filter operates on the terms generated by the tokenizer, so it must be used in combination with a tokenizer.

After defining analyzer_params, you can apply them to a VARCHAR field when defining a collection schema. This allows Milvus to process the text in that field using the specified analyzer for efficient tokenization and filtering. For details, refer to Example use.

Example output

Here’s an example of how the asciifolding filter processes text:

Original text:

"Café Möller serves crème brûlée and piñatas."

Expected output:

["Cafe", "Moller", "serves", "creme", "brulee", "and", "pinatas"]