range

levelup based range index

install

npm install [--save/--save-dev] range-index

examples

data set

| ID | NAME | AGE | SEX | | :--: | :--: | :-: | :-: | | 1 | Divina Ventimiglia | 7 | F | | 2 | Nakisha Robuck | 54 | F | | 3 | Amira Markus | 18 | F | | 4 | Mohamed Kincannon | 60 | M | | 5 | Juana Ardon | 23 | F | | 6 | Hyon Davie | 60 | F | | 7 | Estell Cromer | 18 | F | | 8 | Jacob Neeley | 13 | M | | 9 | Carlene Weatherman | 42 | F | | 10 | Carie Markland | 7 | F |

age/id range index

| AGE | ID | | :-: | :-------: | | 7 | 1, 10 | | 13 | 8 | | 18 | 3, 7 | | 23 | 5 | | 42 | 9 | | 54 | 2 | | 60 | 4, 6 |

as seen in Database Indexes for The Inquisitive Mind

data set

| DOCUMENT | COUNTRIES | | :--------: | :-----------------------------: | | A | Australia, Canada, Portugal | | B | Canada, Portugal, Togo | | C | Algeria, Canada, Portugal, Togo | | D | Algeria, Canada, Togo | | E | Canada, Togo | | F | Togo |

country/document range index

| COUNTRY | DOCUMENTS | | :-------: | :---------------------: | | Algeria | C, D | | Australia | A | | Canada | A, B, C, D, E | | Portugal | A, B, C | | Togo | B, C, D, E, F |

api

var range = require('range-index');

index range(string: location)

var age = range('path/to/location');

void index.put(string/number: value, *: key, function: callback)

age.put(18, 7, function (e) {
  if(e) throw e;
  console.log('index saved successfully');
});

countries.put('Portugal', 'A', function (e) {
  if(e) throw e;
  console.log('index saved successfully');
});

stream index.get(string/number: index)

var user = age.get(18);

user.on('data', function (data) {
  assert(data.value == [3, 7]);
  assert(data.key == 18);
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

var country = countries.get('Portugal');

user.on('data', function (data) {
  assert(data.value == ['A', 'B', 'C']);
  assert(data.key == 'Portugal');
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

index.all()

var users = age.all();

users.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

index.from(start)

var users = age.from(54);

users.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| AGE | ID | | :-: | :-------: | | 54 | 2 | | 60 | 4, 6 |

var from_countries = countries.from('P');

from_countries.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

from_countries.on('error', function (e) {
  throw e;
});

from_countries.on('close', function () {
  console.log('Stream closed')
});

from_countries.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| COUNTRY | DOCUMENTS | | :-------: | :---------------------: | | Portugal | A, B, C | | Togo | B, C, D, E, F |

index.between(start, end)

var users = age.between(13, 23);

users.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| AGE | ID | | :-: | :-------: | | 13 | 8 | | 18 | 3, 7 | | 23 | 5 |

var between_countries = countries.between('A', 'C');

from_countries.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

from_countries.on('error', function (e) {
  throw e;
});

from_countries.on('close', function () {
  console.log('Stream closed')
});

from_countries.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| COUNTRY | DOCUMENTS | | :-------: | :---------------------: | | Algeria | C, D | | Australia | A |

index.until(end)

var users = age.until(18);

users.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

user.on('error', function (e) {
  throw e;
});

user.on('close', function () {
  console.log('Stream closed')
});

user.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| AGE | ID | | :-: | :-------: | | 7 | 1, 10 | | 13 | 8 | | 18 | 3, 7 |

var from_countries = countries.until('P');

from_countries.on('data', function (data) {
  console.log('Age: ', data.key, 'ID\'s: ', data.value)
});

from_countries.on('error', function (e) {
  throw e;
});

from_countries.on('close', function () {
  console.log('Stream closed')
});

from_countries.on('end', function () {
  console.log('Stream closed')
});

returned indexes:

| COUNTRY | DOCUMENTS | | :-------: | :---------------------: | | Algeria | C, D | | Australia | A | | Canada | A, B, C, D, E |

test

npm test

license

MIT