Incomplete Results for Strings that Include Numbers

[thekenshow]

A client site uses part numbers in page titles (e.g., SPK1000) and TNTSearch isn't returning all matches when the first three characters are used.

Test case 1 is a search for "spk", which should return "spk1000" and "spk7457", but only the first appears:

A search for "spk7", returns "spk7457", which should also appear in the previous search:

Test 2 is a search for "739", which should return three results - two instances of "7393 Horn Driver" and 1 with "739" in the body of the text, but instead only returns the latter:

A search for "7393" turns up the first two expected above (two instances of "7393 Horn Driver"):

Thought this might be related to the stemming issue describe here but @ViliusS set me straight.

[ViliusS]

Are you using fuzzy search? Try playing with tntsearch settings a bit to see if one of them makes a difference. That would at least help pinpoint the part of the search algorithm which is failing.

[thekenshow]

Tried the "739" search documented above, with index rebuild + cache clear between tests, with the following:

• fuzzy enabled and then disabled, same result
• phrases enabled and then disabled, same result
• search URL ("/search") directly and using pop-up/overlay, same result
• search type of "auto" and "auto", same result
• steammer enabled and disabled, same result

Here's my settings yaml:

enabled: true
search_route: /search
query_route: /s
built_in_css: true
built_in_js: true
built_in_search_page: true
enable_admin_page_events: true
search_type: auto
fuzzy: true
phrases: true
stemmer: default
display_route: true
display_hits: true
display_time: true
live_uri_update: true
limit: '20'
min: '3'
snippet: '300'
index_page_by_default: true
scheduled_index:
  enabled: false
  at: '* * * * *'
  logs: logs/tntsearch-index.out
filter:
  items:
    - root@.descendants
powered_by: true
search_object_type: Grav

[ViliusS]

I can confirm that there is something strange going on with searches which include numbers. Let's day I have these 2 data points.
"7777777"
"777777777777"

If I search for 777 I get only the first result however it is not highlighted in the context.
If I search for 7777, 77777, 777777 or 7777777 I get only first result and it is now correctly highlighted.
If I search for 77777777 to 777777777777 then I correctly get only second result.

Most probably a bug in TNTSearch library itself. Maybe something with BM25 implementation.

[thekenshow]

Hmmm. Sounds like I may have to implement simple search until this gets resolved. Model numbers are the bread and butter for this client site.

[ViliusS]

I just did a quick debug session and it is definitely a library bug. Most probably a bug in TNTIndexer because the data is already that way in the index. You can try to debug it youself further https://github.com/trilbymedia/grav-plugin-tntsearch/blob/develop/vendor/teamtnt/tntsearch/src/Indexer/TNTIndexer.php or open an issue with them https://github.com/teamtnt/tntsearch

[thekenshow]

Great, thanks for all your help on this. I'll open an issue with https://github.com/teamtnt/tntsearch.

[ViliusS]

I have fixed some highlighter issues found during my tests teamtnt/tntsearch#256, but search with numbers is still broken.

I will try to look at the library code in couple of days if I would find a free and will reply on tntsearch repo.

This issue can be closed here.

[ViliusS]

@thekenshow I've spent some time on this and uncovered another layer of bugs. Try these two patches:
#123
#124

In order to active fuzzy search in the library itself for your case you will also need:
a) apply teamtnt/tntsearch#233 with default fuzzy_no_limit option set to true,
b) and increase Levenshtein distance in the new configuration option to at least 4 or 5.

Other than that, there is nothing we can do at the moment. Proper partial search needs to be implemented by someone in the library.

[thekenshow]

@ViliusS Thanks for diving into this, I'm back to it today and will let you know what happens.