gistfile1.js

print("connected");
var mapFn = function(){
    var minSim = 0.1;
    var fieldName = "text";
    var queryText = "ola";

    var maxSimilarity = function(a,b) {
        var aSize = a.length;
        var bSize = b.length;
        
        if(aSize > bSize) {
            return 1 - ((aSize - bSize) / aSize)
        } else {
            return 1 - ((bSize - aSize) / bSize)
        }
    };

    var levenshtein = function(a, b){
        if(a == b)return 0;
        if(!a.length || !b.length)return b.length || a.length;
        var len1 = a.length + 1,
        len2 = b.length + 1,
        I = 0,
        i = 0,
        d = [[0]],
        c, j, J;
        while(++i < len2)
            d[0][i] = i;
        i = 0;
        while(++i < len1){
            J = j = 0;
            c = a[I];
            d[i] = [i];
            while(++j < len2){
                d[i][j] = Math.min(d[I][j] + 1, d[i][J] + 1, d[I][J] + (c != b[J]));
                ++J;
            };
            ++I;
        };
        return d[len1 - 1][len2 - 1];
    };


    if(maxSimilarity(this[fieldName],queryText) > minSim) {
        var dist = levenshtein(this[fieldName],queryText);
        var metric = 1 - (dist / Math.max(this[fieldName].length, queryText.length))
        if(metric > minSim) {
            var match = {score: metric, match:this };
            emit(this._id, match);
        }
    }
};

db.testsmr.mapReduce(
    mapFn,
    function(k,vals){
        return vals[0];
    },

    {out: { inline : 1}});