new Query(options) → {Object}
creates and returns a Query object that can be used in Collection methods or on its own to operate on items on the server
Parameters:
Name | Type | Description |
---|---|---|
options |
Object | Object that has configuration values used when instantiating a Query object |
- Source:
Returns:
Clearblade.Query the created query
- Type
- Object
Methods
-
columns(Columns, callback)
-
Gets rows of the specified columns
Parameters:
Name Type Description Columns
Object object callback
function Function that handles the response of the server - Source:
Example
Getting values of columns
//This example assumes a collection of items that have the columns name and age. var query = ClearBlade.Query({'collectionName': 'COLLECTIONNAME'}); var callback = function (err, data) { if (err) { throw new Error (data); } else { console.log(data); } }; query.columns(["name","age"]); query.fetch(callback); //gets values in columns name and age
-
equalTo(field, value)
-
Creates an equality clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding an equality clause to a query
var query = ClearBlade.Query(); query.equalTo('name', 'John'); //will only match if an item has an attribute 'name' that is equal to 'John'
-
fetch(callback) → {ClearBlade.Item}
-
Reqests an item or a set of items from the query. Requires that the Query object was initialized with a collection.
Parameters:
Name Type Description callback
function Supplies processing for what to do with the data that is returned from the collection - Source:
Returns:
An array of ClearBlade Items- Type
- ClearBlade.Item
Example
The typical callback
var query = ClearBlade.Query({'collection': 'COLLECTIONID'}); var callback = function (err, data) { if (err) { //error handling } else { console.log(data); } }; query.fetch(callback);
-
greaterThan(field, value)
-
Creates a greater than clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding a greater than clause to a query
var query = ClearBlade.Query(); query.greaterThan('age', 21); //will only match if an item has an attribute 'age' that is greater than 21
-
greaterThanEqualTo(field, value)
-
Creates a greater than or equality clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding a greater than or equality clause to a query
var query = ClearBlade.Query(); query.greaterThanEqualTo('age', 21); //will only match if an item has an attribute 'age' that is greater than or equal to 21
-
lessThan(field, value)
-
Creates a less than clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding a less than clause to a query
var query = ClearBlade.Query(); query.lessThan('age', 50); //will only match if an item has an attribute 'age' that is less than 50
-
lessThanEqualTo(field, value)
-
Creates a less than or equality clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding a less than or equality clause to a query
var query = ClearBlade.Query(); query.lessThanEqualTo('age', 50); //will only match if an item has an attribute 'age' that is less than or equal to 50
-
matches(field, pattern)
-
Creates an regular expression matching clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare pattern
String String or Number that is used to compare against - Source:
Example
Adding an regex matching clause to a query
var query = ClearBlade.Query(); query.matches('name', 'Smith$'); //will only match if an item has an attribute 'name' that That ends in 'Smith'
-
notEqualTo(field, value)
-
Creates a not equal clause in the query object
Parameters:
Name Type Description field
String String defining what attribute to compare value
String String or Number that is used to compare against - Source:
Example
Adding a not equal clause to a query
var query = ClearBlade.Query(); query.notEqualTo('name', 'Jim'); //will only match if an item has an attribute 'name' that is not equal to 'Jim'
-
or(that)
-
chains an existing query object to the Query object in an or
Parameters:
Name Type Description that
Query Query object that will be added in disjunction to this query object - Source:
Example
Chaining two queries together in an or
var query1 = ClearBlade.Query(); var query2 = ClearBlade.Query(); query1.equalTo('name', 'John'); query2.equalTo('name', 'Jim'); query1.or(query2); //will match if an item has an attribute 'name' that is equal to 'John' or 'Jim'
-
remove(callback)
-
Removes an item or set of items from the Query
Parameters:
Name Type Description callback
function Function that handles the response from the server - Source:
Example
Removing an item in a collection
//This example assumes that you have a collection with the item whose 'name' attribute is 'John' var query = ClearBlade.Query({'collection': 'COLLECTIONID'}); query.equalTo('name', 'John'); var callback = function (err, data) { if (err) { throw new Error (data); } else { console.log(data); } }; query.remove(callback); //removes every item whose 'name' attribute is equal to 'John'
-
setPage(pageSize, pageNum)
-
Set the pagination options for a Query.
Parameters:
Name Type Description pageSize
int Number of items per response page. The default is 100. pageNum
int Page number, taking into account the page size. The default is 1. - Source:
-
update(changes, callback)
-
Updates an existing item or set of items. Requires that a collection was set when the Query was initialized.
Parameters:
Name Type Description changes
Object Object representing the attributes that you want changed callback
function Function that handles the response of the server - Source:
Example
Updating a set of items
//This example assumes a collection of items that have the columns name and age. var query = ClearBlade.Query({'collection': 'COLLECTIONID'}); query.equalTo('name', 'John'); var changes = { age: 23 }; var callback = function (err, data) { if (err) { throw new Error (data); } else { console.log(data); } }; query.update(changes, callback); //sets John's age to 23