new Resultset(collection)
Resultset class allowing chainable queries. Intended to be instanced internally. Collection.find(), Collection.where(), and Collection.chain() instantiate this.
Parameters:
Name | Type | Description |
---|---|---|
collection |
Collection | The collection which this Resultset will query against. |
- Source:
Example
mycollection.chain()
.find({ 'doors' : 4 })
.where(function(obj) { return obj.name === 'Toyota' })
.data();
Members
branch
Alias of copy()
- Source:
Methods
compoundsort(properties) → {Resultset}
Allows sorting a resultset based on multiple columns.
Parameters:
Name | Type | Description |
---|---|---|
properties |
array | array of property names or subarray of [propertyname, isdesc] used evaluate sort order |
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
// to sort by age and then name (both ascending)
rs.compoundsort(['age', 'name']);
// to sort by age (ascending) and then by name (descending)
rs.compoundsort(['age', ['name', true]]);
copy() → {Resultset}
copy() - To support reuse of resultset in branched query situations.
- Source:
Returns:
Returns a copy of the resultset (set) but the underlying document references will be the same.
- Type
- Resultset
count() → {number}
count() - returns the number of documents in the resultset.
- Source:
Returns:
The number of documents in the resultset.
- Type
- number
Example
var over30Count = users.chain().find({ age: { $gte: 30 } }).count();
docs(optionsopt) → {array}
Terminates the chain and returns array of filtered documents
Parameters:
Name | Type | Attributes | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
object |
<optional> |
allows specifying 'forceClones' and 'forceCloneMethod' options. Properties
|
- Source:
Returns:
Array of documents in the resultset
- Type
- array
Example
var resutls = users.chain().find({ age: 34 }).data();
eqJoin(joinData, leftJoinKey, rightJoinKey, mapFunopt, dataOptionsopt) → {Resultset}
eqJoin() - Left joining two sets of data. Join keys can be defined or calculated properties eqJoin expects the right join key values to be unique. Otherwise left data will be joined on the last joinData object with that key
Parameters:
Name | Type | Attributes | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
joinData |
Array | Resultset | Collection | Data array to join to. |
|||||||||||||
leftJoinKey |
string | function | Property name in this result set to join on or a function to produce a value to join on |
|||||||||||||
rightJoinKey |
string | function | Property name in the joinData to join on or a function to produce a value to join on |
|||||||||||||
mapFun |
function |
<optional> |
(Optional) A function that receives each matching pair and maps them into output objects - function(left,right){return joinedObject} |
||||||||||||
dataOptions |
object |
<optional> |
options to data() before input to your map function Properties
|
- Source:
Returns:
A resultset with data in the format [{left: leftObj, right: rightObj}]
- Type
- Resultset
Example
var db = new controldb('sandbox.db');
var products = db.addCollection('products');
var orders = db.addCollection('orders');
products.insert({ productId: "100234", name: "flywheel energy storage", unitCost: 19999.99 });
products.insert({ productId: "140491", name: "300F super capacitor", unitCost: 129.99 });
products.insert({ productId: "271941", name: "fuel cell", unitCost: 3999.99 });
products.insert({ productId: "174592", name: "390V 3AH lithium bank", unitCost: 4999.99 });
orders.insert({ orderDate : new Date("12/1/2017").getTime(), prodId: "174592", qty: 2, customerId: 2 });
orders.insert({ orderDate : new Date("4/15/2016").getTime(), prodId: "271941", qty: 1, customerId: 1 });
orders.insert({ orderDate : new Date("3/12/2017").getTime(), prodId: "140491", qty: 4, customerId: 4 });
orders.insert({ orderDate : new Date("7/31/2017").getTime(), prodId: "100234", qty: 7, customerId: 3 });
orders.insert({ orderDate : new Date("8/3/2016").getTime(), prodId: "174592", qty: 3, customerId: 5 });
var mapfun = function(left, right) {
return {
orderId: left.$ctrl,
orderDate: new Date(left.orderDate) + '',
customerId: left.customerId,
qty: left.qty,
productId: left.prodId,
prodName: right.name,
prodCost: right.unitCost,
orderTotal: +((right.unitCost * left.qty).toFixed(2))
};
};
// join orders with relevant product info via eqJoin
var orderSummary = orders.chain().eqJoin(products, "prodId", "productId", mapfun).data();
console.log(orderSummary);
find(query, firstOnlyopt) → {Resultset}
Used for querying via a mongo-style query object.
Parameters:
Name | Type | Attributes | Description |
---|---|---|---|
query |
object | A mongo-style query object used for filtering current results. |
|
firstOnly |
boolean |
<optional> |
(Optional) Used by collection.findOne() |
- Source:
Returns:
this resultset for further chain ops.
- Type
- Resultset
Example
var over30 = users.chain().find({ age: { $gte: 30 } }).data();
map(mapFun, dataOptionsopt)
Applies a map function into a new collection for further chaining.
Parameters:
Name | Type | Attributes | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
mapFun |
function | javascript map function |
|||||||||||||
dataOptions |
object |
<optional> |
options to data() before input to your map function Properties
|
- Source:
Example
var orders.chain().find({ productId: 32 }).map(function(obj) {
return {
orderId: $ctrl,
productId: productId,
quantity: qty
};
});
mapReduce(mapFunction, reduceFunction) → {value}
data transformation via user supplied functions
Parameters:
Name | Type | Description |
---|---|---|
mapFunction |
function | this function accepts a single document for you to transform and return |
reduceFunction |
function | this function accepts many (array of map outputs) and returns single value |
- Source:
Returns:
The output of your reduceFunction
- Type
- value
Example
var db = new controldb("order.db");
var orders = db.addCollection("orders");
orders.insert([{ qty: 4, unitCost: 100.00 }, { qty: 10, unitCost: 999.99 }, { qty: 2, unitCost: 49.99 }]);
function mapfun (obj) { return obj.qty*obj.unitCost };
function reducefun(array) {
var grandTotal=0;
array.forEach(function(orderTotal) { grandTotal += orderTotal; });
return grandTotal;
}
var grandOrderTotal = orders.chain().mapReduce(mapfun, reducefun);
console.log(grandOrderTotal);
remove() → {Resultset}
Removes all document objects which are currently in resultset from collection (as well as resultset)
- Source:
Returns:
this (empty) resultset for further chain ops.
- Type
- Resultset
Example
// remove users inactive since 1/1/2001
users.chain().find({ lastActive: { $lte: new Date("1/1/2001").getTime() } }).remove();
simplesort(propname, options) → {Resultset}
Simpler, loose evaluation for user to sort based on a property name. (chainable). Sorting based on the same lt/gt helper functions used for binary indices.
Parameters:
Name | Type | Description | |||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
propname |
string | name of property to sort by. |
|||||||||||||||||||||||||
options |
object | bool | boolean to specify if isdescending, or options object Properties
|
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
var results = users.chain().simplesort('age').data();
sort(comparefun) → {Resultset}
User supplied compare function is provided two documents to compare. (chainable)
Parameters:
Name | Type | Description |
---|---|---|
comparefun |
function | A javascript compare function used for sorting. |
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
rslt.sort(function(obj1, obj2) {
if (obj1.name === obj2.name) return 0;
if (obj1.name > obj2.name) return 1;
if (obj1.name < obj2.name) return -1;
});
transform(transform, parametersopt) → {Resultset}
transform() - executes a named collection transform or raw array of transform steps against the resultset.
Parameters:
Name | Type | Attributes | Description |
---|---|---|---|
transform |
string | array | name of collection transform or raw transform array |
|
parameters |
object |
<optional> |
(Optional) object property hash of parameters, if the transform requires them. |
- Source:
Returns:
either (this) resultset or a clone of of this resultset (depending on steps)
- Type
- Resultset
Example
users.addTransform('CountryFilter', [
{
type: 'find',
value: {
'country': { $eq: '[%lktxp]Country' }
}
},
{
type: 'simplesort',
property: 'age',
options: { desc: false}
}
]);
var results = users.chain().transform("CountryFilter", { Country: 'fr' }).data();
update(updateFunction) → {Resultset}
Used to run an update operation on all documents currently in the resultset.
Parameters:
Name | Type | Description |
---|---|---|
updateFunction |
function | User supplied updateFunction(obj) will be executed for each document object. |
- Source:
Returns:
this resultset for further chain ops.
- Type
- Resultset
Example
users.chain().find({ country: 'de' }).update(function(user) {
user.phoneFormat = "+49 AAAA BBBBBB";
});
where(fun) → {Resultset}
where() - Used for filtering via a javascript filter function.
Parameters:
Name | Type | Description |
---|---|---|
fun |
function | A javascript function used for filtering current results by. |
- Source:
Returns:
this resultset for further chain ops.
- Type
- Resultset
Example
var over30 = users.chain().where(function(obj) { return obj.age >= 30; }.data();
(static) Collection#compoundsort(properties) → {Resultset}
Allows sorting a resultset based on multiple columns.
Parameters:
Name | Type | Description |
---|---|---|
properties |
array | array of property names or subarray of [propertyname, isdesc] used evaluate sort order |
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
// to sort by age and then name (both ascending)
rs.compoundsort(['age', 'name']);
// to sort by age (ascending) and then by name (descending)
rs.compoundsort(['age', ['name', true]]);
(static) Collection#copy() → {Resultset}
copy() - To support reuse of resultset in branched query situations.
- Source:
Returns:
Returns a copy of the resultset (set) but the underlying document references will be the same.
- Type
- Resultset
(static) Collection#docs(optionsopt) → {array}
Terminates the chain and returns array of filtered documents
Parameters:
Name | Type | Attributes | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
object |
<optional> |
allows specifying 'forceClones' and 'forceCloneMethod' options. Properties
|
- Source:
Returns:
Array of documents in the resultset
- Type
- array
Example
var resutls = users.chain().find({ age: 34 }).data();
(static) Collection#find(query, firstOnlyopt) → {Resultset}
Used for querying via a mongo-style query object.
Parameters:
Name | Type | Attributes | Description |
---|---|---|---|
query |
object | A mongo-style query object used for filtering current results. |
|
firstOnly |
boolean |
<optional> |
(Optional) Used by collection.findOne() |
- Source:
Returns:
this resultset for further chain ops.
- Type
- Resultset
Example
var over30 = users.chain().find({ age: { $gte: 30 } }).data();
(static) Collection#map(mapFun, dataOptionsopt)
Applies a map function into a new collection for further chaining.
Parameters:
Name | Type | Attributes | Description | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
mapFun |
function | javascript map function |
|||||||||||||
dataOptions |
object |
<optional> |
options to data() before input to your map function Properties
|
- Source:
Example
var orders.chain().find({ productId: 32 }).map(function(obj) {
return {
orderId: $ctrl,
productId: productId,
quantity: qty
};
});
(static) Collection#simplesort(propname, options) → {Resultset}
Simpler, loose evaluation for user to sort based on a property name. (chainable). Sorting based on the same lt/gt helper functions used for binary indices.
Parameters:
Name | Type | Description | |||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
propname |
string | name of property to sort by. |
|||||||||||||||||||||||||
options |
object | bool | boolean to specify if isdescending, or options object Properties
|
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
var results = users.chain().simplesort('age').data();
(static) Collection#sort(comparefun) → {Resultset}
User supplied compare function is provided two documents to compare. (chainable)
Parameters:
Name | Type | Description |
---|---|---|
comparefun |
function | A javascript compare function used for sorting. |
- Source:
Returns:
Reference to this resultset, sorted, for future chain operations.
- Type
- Resultset
Example
rslt.sort(function(obj1, obj2) {
if (obj1.name === obj2.name) return 0;
if (obj1.name > obj2.name) return 1;
if (obj1.name < obj2.name) return -1;
});
(static) Collection#transform(transform, parametersopt) → {Resultset}
transform() - executes a named collection transform or raw array of transform steps against the resultset.
Parameters:
Name | Type | Attributes | Description |
---|---|---|---|
transform |
string | array | name of collection transform or raw transform array |
|
parameters |
object |
<optional> |
(Optional) object property hash of parameters, if the transform requires them. |
- Source:
Returns:
either (this) resultset or a clone of of this resultset (depending on steps)
- Type
- Resultset
Example
users.addTransform('CountryFilter', [
{
type: 'find',
value: {
'country': { $eq: '[%lktxp]Country' }
}
},
{
type: 'simplesort',
property: 'age',
options: { desc: false}
}
]);
var results = users.chain().transform("CountryFilter", { Country: 'fr' }).data();