# Collection.get / Query.get
Obtains a collection of data, or a collection of data filtered based on the query criteria.
If limit is not specified, a maximum of 20 records are returned.
If skip is not specified, the records are returned from the record 0, and skip is generally used for paging. Refer to Sample code 2.
Function signature is shown as below:
function get(options?: object): Promise<Result>
Parameter description
options
is an optional parameter, an object with the following format. For example: if one of success
, fail
and complete
is passed in, it means the callback style is used, and Promise
is not returned.
Field | Type | Required | Default | Description |
---|---|---|---|---|
success | Function | No | Callback succeeds. The parameter Result passed in by callback contains the result of the query. The Result is defined as below. | |
fail | Function | No | Callback fails | |
complete | Function | No | Callback function when call completes (always executed whether call succeeds or fails) |
Description of return value
If the options
parameter is not passed, or the incoming options
parameter does not have a success
, fail
or complete
field, a Promise
will be returned or otherwise no value is returned. The results of resolve
and reject
for Promise
are defined as below:
Result Description | |
---|---|
resolve | The result of query. The Result is defined as below. |
reject | Reason for failure |
Result description
The result of success
callback and Result
of resolve
for Promise
are objects with the following structure:
Field | Type | Description |
---|---|---|
data | Array | The result array of a query. Each element of data is an Object representing a record. |
Sample code 1
Get my to-do list
Callback style
const db = wx.cloud.database()
db.collection('todos').where({
_openid: 'xxx' // Enter the current user openid
}).get({
success: function(res) {
console.log(res.data)
}
})
Promise style
const db = wx.cloud.database()
db.collection('todos').where({
_openid: 'xxx' // Enter the current user openid
}).get().then(res => {
console.log(res.data)
})
Sample code 2: Get data by paging
To get your to-do list on page 2, if, for example, there are ten to-dos on page 1, and you can specify to skip 10 to-dos.
// Promise style
const db = wx.cloud.database()
db.collection('todos')
.where({
_openid: 'xxx', // Enter the current user openid
})
.skip(10) // The first 10 to-dos in the result set are skipped, and results are returned from the 11th one onwards.
.limit(10) // A maximum of 10 results are returned.
.get()
.then(res => {
console.log(res.data)
})
.catch(err => {
console.error(err)
})