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Re: [geowave-dev] Indexing Textual Data

Hi Joel,
How do you want to search the text? We do have some support for an N-grams indexing technique on textual fields [1]. The challenge in a key-value store for textual indices is the ability to support any regular _expression_ with arbitrarily placed wildcards (ie. more than simply prefix and suffix).  Here is some discussion on how we decided to tackle it [2].  However, this gets complex and at the moment this isn't really a well-advertised feature. We are primarily focused on multidimensional numeric indices, with textual indexing on large corpus being well-supported by projects like ElasticSearch.  Keep in mind that you can always run textual filtered queries through GeoWave, it just will use the spatial or spatiotemporal index and need to apply additional server-side filtering if you want to use regular expressions. If you had certain queries that are predominantly text constrained it would generally be best to utilize an ElasticSearch index.

1) https://github.com/locationtech/geowave/blob/v0.9.5/core/store/src/main/java/mil/nga/giat/geowave/core/store/index/text/TextIndexStrategy.java
2) https://github.com/locationtech/geowave/wiki/Secondary-Indexing#ilike-and-like-_expression_-processing

On Mon, Aug 14, 2017 at 11:40 AM, Joel Folkerts <joel.folkerts@xxxxxxxxx> wrote:
Good morning. 

 I am reviewing the feasibility of using GeoWave to index large volumes data currently stored in CSVs that contain a temporal column, spatial (lat/lon) column, and a column containing textual data. Apart from getting the CSV data into GeoWave (which I can work through), I am concerned that I won't be able to create an index for the textual data. I've reviewed all of the documentation and source code and only see spatial/temporal indices referenced. Is it possible to also create a textual index?

-Joel

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