Text index of quotes in memory in Go

Recently I needed to implement search by the beginning of a string, in fact WHERE name LIKE '%'. It was a search by the name of exchange symbols (AAPL, AMZN, EUR / USD, etc.). I wanted the search to work quickly and not load the database again. As a result, I came to the implementation of tree search in memory, and I'll tell you about this.

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• AAA (BetaShares Australian High Interest Cash ETF, ASX), 

• AAA (All Active Asset Capital LTD, LSE).

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• AAL

• AAALF

• AAAP

• AAB

• AAP

• AAPJ

• AAPL

• AAPT

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WHERE name LIKE '%'. , , .

• “EUR”, “EUR”, “EUR/USD”, “USD/EUR”. , .

• , . , “APL”, “APL”, “AAPL” (Apple).

• .

“EUR”, “EUR”, “EUR/USD”, “USD/EUR”, : . , “USD/EUR”, : “usd eur”, “eur”. “Grupo Financiero Galicia SA” “Grupo Financiero Galicia SA”, “Financiero Galicia SA”, “Galicia SA”, “SA”.

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1. SearchSymbolIndex .

2. SearchPopularIndex (10% ).

3. SearchInstrumentIndex .

— .

var searchedData []searchindex.SearchData

searchedData = r.SearchSymbolIndex.Search(searchindex.SearchParams{
    Text: key,
    OutputSize: outputSize,
    Matching: searchsymbol.Strict,
})

searchedData = r.SearchPopularIndex.Search(searchindex.SearchParams{
    Text: key,
    OutputSize: outputSize,
    Matching: searchsymbol.Beginning,
    StartValues: searchedData,
})

searchedData = r.SearchSymbolIndex.Search(searchindex.SearchParams{
    Text: key,
    OutputSize: outputSize,
    Matching: searchindex.Beginning,
    StartValues: searchedData,
})

searchedData = r.SearchInstrumentIndex.Search(searchindex.SearchParams{
    Text: key,
    OutputSize: outputSize,
    Matching: searchindex.Beginning,
    StartValues: searchedData,
})

StartValues — , , , , , (OutputSize).

searchindex.Strict —  . 

searchindex.Beginning — .

, . 300 . , .

, 55000 2 , . 4 100-200 ( http ), .

This search is currently used in the financial api for developers, an example can be viewed on this page where you can try it live.