Does App search support substring search?

[Gerardo_Zenobi]

Hi there

I wanted to know if App Search supported substring search ? E.g. if a user searches for “note”, this would find records with attributes containing “notepad” or “notebook”, but it would also match “keynote”.

For more context:

• Find strings within strings faster with the Elasticsearch wildcard field | Elastic Blog
• Substring search in Elasticsearch - Hashnode

Thanks in advance.

[Carlos_D (Carlos)]

Hi @Gerardo_Zenobi , nice to see you again!

App Search does not support wildcard search. It does, however, support prefix matching as part of App Search precision tuning.

So, in your example, you would potentially get matches for "notepad" and "notebook" for a "note" query, but you would not find matches for "keynote".

Keep in mind that there are several strategies being done under the hood in Enterprise Search:

• Prefixing
• Stemming (finding word roots, so a query for "jumping" gets results for "jump", "jumps" and "jumping")
• Delimiters removal (so "e-commerce" matches "ecommerce")
• Word joiners (so "FY 2022" would match a document with "FY2022")

These strategies are used depending on the precision level for the query.

You can experiment with precision tuning for checking the results obtained for different queries in an Engine.

[Gerardo_Zenobi]

Hi @Carlos_D, nice to see you too

I am sorry but I think I didn't understand completely ^^

For the query "note" ... you would not find matches for "keynote".

Wouldn't the mentioned strategy Prefixing help in this use case?

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In general terms, then, would you say substring search is not supported then?

Thanks again

[Carlos_D (Carlos)]

Wouldn't the mentioned strategy Prefixing help in this use case?

I'm afraid not. You can think of prefixing as using a wildcard at the end of the query (in this case, "note*" would not match "keynote").

In general terms, then, would you say substring search is not supported then?

Substring search is not supported, just prefixing.