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# CountDataItems

# Package: externalDatabases

# Namespace: ExternalDatabaseService

# Method link: https://dev.wix.com/docs/api-reference/business-solutions/cms/external-databases/external-database-service-plugin/count-data-items.md

## Introduction

Counts the number of items in the specified data collection that match the filtering preferences.

---

## REST API

### Schema

```
 Method: countDataItems
 Description: Counts the number of items in the specified data collection that match the filtering preferences.
 URL: null
 Method: POST
 # Note: If the parameter `a.b` is listed under required parameters, `b` is only required if `a` is also present.
 Required parameters:  collectionId, filter, consistentRead
 Method parameters: 
   param name: collectionId | type: collectionId | description: GUID of the collection to query. | required: true
   param name: consistentRead | type: consistentRead | description: Whether to retrieve data from the primary database instance. This decreases performance but ensures data retrieved is up-to-date even immediately after an update. Applicable if the external database is eventually consistent. | required: true
   param name: filter | type: filter | description: Filter to specify which items to count. See [API Query Language](https://dev.wix.com/docs/rest/articles/getting-started/api-query-language.md#the-filter-section) for more information about handling data queries. | required: true
 Return type: CountDataItemsResponse
  - name: totalCount | type: integer | description: Number of items that match the query. 


```

### Examples

### Count items
```curl
curl -X POST https://external-db.example.com/v3/items/count  \
    -H 'Content-Type: application/json;charset=UTF-8' \
    -H 'Authorization: <AUTH>' \
    -d '{
  "collectionId": "cities",
  "filter": {
  },
  "consistentRead": false
}'
```

### Count items with a filter
```curl
curl -X POST https://external-db.example.com/v3/items/count  \
    -H 'Content-Type: application/json;charset=UTF-8' \
    -H 'Authorization: <AUTH>' \
    -d '{
  "collectionId": "cities",
  "filter": {
    "country": "US"
  },
  "consistentRead": false
}'
```

---

## JavaScript SDK

### Schema

```
 Method: wixClientAdmin.externalDatabases.ExternalDatabaseService.countDataItems(request, metadata)
 Description: Counts the number of items in the specified data collection that match the filtering preferences.
 Method parameters:
   param name: metadata | type: Context | description: this message is not directly used by any service, it exists to describe the expected parameters that SHOULD be provided to invoked Velo methods as part of open-platform. e.g. SPIs, event-handlers, etc.. NOTE: this context object MUST be provided as the last argument in each Velo method signature.  Example: ```typescript export function wixStores_onOrderCanceled({ event, metadata }: OrderCanceledEvent) { ... } ``` 
        - name: requestId | type: string | description: A unique identifier of the request. You may print this GUID to your logs to help with future debugging and easier correlation with Wix's logs. 
        - name: currency | type: string | description: [ISO 4217](https://en.wikipedia.org/wiki/ISO_4217) 3-letter currency code. 
        - name: identity | type: IdentificationData | description: An object that describes the identity that triggered this request. 
           - ONE-OF: 
              - name: anonymousVisitorId | type: string | description: GUID of a site visitor that has not logged in to the site. 
              - name: memberId | type: string | description: GUID of a site visitor that has logged in to the site. 
              - name: wixUserId | type: string | description: GUID of a Wix user (site owner, contributor, etc.). 
              - name: appId | type: string | description: GUID of an app. 
        - name: languages | type: array | description: A string representing a language and region in the format of `"xx-XX"`. First 2 letters represent the language code according to ISO 639-1. This is followed by a dash "-", and then a by 2 capital letters representing the region according to ISO 3166-2. For example, `"en-US"`. 
        - name: instanceId | type: string | description: The service provider app's instance GUID. 
   param name: request | type: CountDataItemsRequest   
        - name: collectionId | type: string | description: GUID of the collection to query. 
        - name: filter | type: object | description: Filter to specify which items to count. See [API Query Language](https://dev.wix.com/docs/rest/articles/getting-started/api-query-language.md#the-filter-section) for more information about handling data queries. 
        - name: consistentRead | type: boolean | description: Whether to retrieve data from the primary database instance. This decreases performance but ensures data retrieved is up-to-date even immediately after an update. Applicable if the external database is eventually consistent. 
 Return type: PROMISE<CountDataItemsResponse>
  - name: totalCount | type: integer | description: Number of items that match the query. 


```

### Examples

### Example of a `totalCount` return value
```javascript
import { externalDatabase } from '@wix/data/service-plugins';

externalDatabase.provideHandlers({

  countDataItems: async ( payload ) => {
    const {request, metadata} = payload;
        // Use the `request` and `metadata` received from Wix and
        // apply custom logic.
      return {
        // Return your response exactly as documented to integrate with Wix.
        // Return value example:
        totalCount: 42
      }
    }
});

```

### countDataItems (self-hosted)
Self-hosted SDK calls require you to [create a client](https://dev.wix.com/docs/sdk/articles/work-with-the-sdk/about-the-wix-client.md).

```javascript
import { createClient } from '@wix/sdk';
import { externalDatabase } from '@wix/data/service-plugins';
// Import the auth strategy for the relevant access type
// Import the relevant host module if needed

const myWixClient = createClient ({
  modules: { externalDatabase },
  // Include the auth strategy and host as relevant
});


async function countDataItems(request,metadata) {
  const response = await myWixClient.externalDatabase.countDataItems(request,metadata);
};
```

---