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Search

You can search in your index by passing a query object to the search function like so:

q.query = {
   AND: {'*': ['usa']}     // search for string 'usa' in all ('*') fields
}
si.search(q) // <- si is a readable stream that emits documents sorted by relevance
  .on('data', function(doc) {
    // do some stuff with doc
  })

Search types

Search index supports several types of search:

Simple Search

Use the wildcard token ('*') to do simple searches across all fields

q.query = {
  AND: {'*': ['reagan']}
}

(shhhh! search index will also accept "lazy" queries):

q = 'reagan'  // the same as the query above

Fielded Search

You can search on specified fields

Every <fieldName>: [<searchterms>] in the query must return true in order for the corresponding document to be included in the search results. In the example below, only documents containing the word reagan in the title field AND the word usa in the body field will be returned.

q.query = 
  {
    AND: {
      'title': ['reagan'],
      'body':  ['usa']
    }
  }
}

Boolean Search (AND, OR, NOT)

You can construct boolean AND, OR and NOT queries:

q.query = [                   // Each array element is an OR condition
  {
    AND: {             
      'title': ['reagan'],    // 'reagan' AND 'ussr'   
      'body':  ['ussr']
    },
    NOT: {
      'body':  ['usa']        // but NOT 'usa' in the body field
    }
  },
  {                           // OR this condition
    AND: {                  
      'title': ['gorbachev'], // 'gorbachev' AND 'ussr'
      'body':  ['ussr']
    },
    NOT: {
      'body':  ['usa']        // NOT 'usa' in the body field
    }
  }
}

Multi-word Search

To search for more than one term, the search string must be tokenised into an array

A search on <fieldName> for [<searchterms>] returns true if and only if all of [<searchterms>] appear in <fieldName>

q.query = {
  AND: {'*': ['usa', 'reagan']}
}

Phrase Search

Use one array element per phrase. You can search for combinations of phrases if desired.

q.query = {
  AND: {'*': ['ronald reagan']}
}

Boosted Search

You can boost an OR condition of your search string like so. The boost value is a positive or negative number that is summed into the final hit score.

query: [
  {
    AND:   {'name':        ['watch']},
    BOOST: 10
  },
  {
    AND:   {'description': ['swiss', 'watch']}
  }
]

Filters

Filters are a way of limiting the resultset, using the categories/buckets that the same resultset makes available. Think of them as the query that must be called when you select buckets/categories.

query: {
  AND: {
    'description': ['swiss', 'watch'],
    'price': [{
       gte: '1000',
       lte: '8'
    }]
  }
}
  • gte: greater than or equal to
  • lte: less than or equal to

Note that filters work by selecting ranges of strings- so the example above would return prices of '70000' for example

Paging

You can handle paging by setting an offset and a pageSize. For example, the following would give you page 3 of a resultset, where the page size is 50:

q.query    = {AND: {'*': ['usa']}}
q.offset   = 100;
q.pageSize = 50;

Gotchas

Common error when test-querying your search solution

When you have indexed some documents, you want to check if your search is working, and do a couple of test queries. Remember then, to not use any of the stopwords. These are words that hold little meaning and are therefore left out of the index. This is the search-index stopword list for English, and here are all the available stopword languages.

q.query = {
  AND: {'*': ['and']}
}

And since there iss an inherent logical AND when having multiple words in your query, it only takes one word from the stopword-list to get zero results back.

q.query = {
  AND: {'*': ['and', 'meaningful']}
}