Awesome
range
level 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(level: db)
var db = level('path/to/location', {
createIfMissing: true,
valueEncoding: 'json',
keyEncoding: 'binary'
})
var age = range(db);
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')
});
with kordon/cursor:
age.get(18).pipe(cursor.all(function (keys, values, data) {
assert.equal(e, null);
assert(values[0] == [3, 7]);
assert(keys[0] == 18);
}));
countries.get('Portugal').pipe(cursor.all(function (keys, values, data) {
assert.equal(e, null);
assert(values[0] == ['A', 'B', 'C']);
assert(key[0] == 'Portugal');
}));
stream index.all()
age.all().pipe(cursor.each(function (key, value, data) {
console.log('Age: ', key, 'ID\'s: ', value);
}, function () {
// end
}));
stream index.from(start)
age.from(54).pipe(cursor.each(function (key, value, data) {
console.log('Age: ', key, 'ID\'s: ', value);
}, function () {
// end
}));
returned indexes:
| AGE | ID |
|---|---|
| 54 | 2 |
| 60 | 4, 6 |
countries.from('P').pipe(cursor.each(function (key, value, data) {
console.log('Country: ', key, 'Documents: ', value);
}, function () {
// end
}));
returned indexes:
| COUNTRY | DOCUMENTS |
|---|---|
| Portugal | A, B, C |
| Togo | B, C, D, E, F |
stream index.between(start, end)
age.between(13, 23).pipe(cursor.each(function (key, value, data) {
console.log('Age: ', key, 'ID\'s: ', value);
}, function () {
// end
}));
returned indexes:
| AGE | ID |
|---|---|
| 13 | 8 |
| 18 | 3, 7 |
| 23 | 5 |
countries.between('A', 'C').pipe(cursor.each(function (key, value, data) {
console.log('Country: ', key, 'Documents: ', value);
}, function () {
// end
}));
returned indexes:
| COUNTRY | DOCUMENTS |
|---|---|
| Algeria | C, D |
| Australia | A |
stream index.until(end)
age.until(18).pipe(cursor.each(function (key, value, data) {
console.log('Age: ', key, 'ID\'s: ', value);
}, function () {
// end
}));
returned indexes:
| AGE | ID |
|---|---|
| 7 | 1, 10 |
| 13 | 8 |
| 18 | 3, 7 |
countries.until('P').pipe(cursor.each(function (key, value, data) {
console.log('Country: ', key, 'Documents: ', value);
}, function () {
// end
}));
returned indexes:
| COUNTRY | DOCUMENTS |
|---|---|
| Algeria | C, D |
| Australia | A |
| Canada | A, B, C, D, E |
void index.del(string/number: value, *: key, function: callback)
age.del(18, 7, function (e) {
if(e) throw e;
console.log('index deleted successfully');
});
countries.del('Portugal', 'A', function (e) {
if(e) throw e;
console.log('index deleted successfully');
});
license
MIT