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Retrieve a table row using the Web API

  • Άρθρο

Use a GET request to retrieve data for a record specified as the resource with a unique identifier. When retrieving a table row (entity record), you can also request specific properties and expand navigation properties to return properties from related records in different tables.

Note

For information about retrieving table definitions, see Query table definitions using the Web API.

Basic retrieve

The following example returns data for an account entity record with the primary key value equal to 00000000-0000-0000-0000-000000000001:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)

This example returns all the properties for account record, which isn't a performance best practice. You should always use the $select system query option to limit the properties returned while retrieving data. This is especially important when retrieving multiple rows of data. More information: Query Data using the Web API.

Retrieve specific properties

To limit the properties returned when you retrieve data with a GET request, use the $select system query option with a comma-separated list of property names. Requesting only the properties you need is an important performance best practice. If you don't specify properties to return, all properties are returned.

The following example retrieves name and revenue properties for the account entity with the primary key value equal to 00000000-0000-0000-0000-000000000001:

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)?$select=name,revenue HTTP/1.1
Accept: application/json
Content-Type: application/json; charset=utf-8
OData-MaxVersion: 4.0
OData-Version: 4.0

Response:

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal
OData-Version: 4.0

{
"@odata.context": "[Organization URI]/api/data/v9.2/$metadata#accounts(name,revenue)/$entity",  
"@odata.etag": "W/\"502186\"",  
"name": "A. Datum Corporation (sample)",  
"revenue": 10000,  
"accountid": "00000000-0000-0000-0000-000000000001",  
"_transactioncurrencyid_value":"b2a6b689-9a39-e611-80d2-00155db44581"  
}

When you request certain types of properties, you can expect more read-only properties to be returned automatically.

If you request a money value, the _transactioncurrencyid_value lookup property is returned. This property contains only the GUID value of the transaction currency, so you could use it to retrieve information about the currency using the transactioncurrency EntityType. Alternatively, you can get more data in the same request by requesting annotations.

If you request a property that's part of a composite attribute for an address, you get the composite property, too. For example, if your query requests the address1_line1 property for a contact, the address1_composite property is also returned.

Retrieve record using an alternate key

If an entity has an alternate key defined, you can use it instead of the unique identifier to retrieve, update, or delete the entity. By default, no alternate keys are configured for entities. Alternate keys are available only if your organization or a solution adds them.

Alternate key values with the following characters /,<,>,*,%,&,:,\\,?,+ aren't currently supported.

For example, if the Contact entity has an alternate key definition that includes both the firstname and emailaddress1 properties, you can retrieve the contact using a query with data provided for those keys:

GET [Organization URI]/api/data/v9.2/contacts(firstname='Joe',emailaddress1='abc@example.com')

If the alternate key definition contains a lookup type field (for example, the primarycontactid property for the account entity), you can retrieve the account using the Lookup properties, as in the following example:

GET [Organization URI]/api/data/v9.2/accounts(_primarycontactid_value=00000000-0000-0000-0000-000000000001)

Retrieve documents in storage partitions

When you retrieve a record in an elastic table that's stored in a partition, be sure to specify the partition key.

Retrieve a single property value

When you only need to retrieve the value of a single property, you can append the name of the property to the entity URI. Reducing the amount of data returned is a performance best practice.

The following example returns only the value of the name property for an account entity:

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)/name HTTP/1.1
Accept: application/json
OData-MaxVersion: 4.0
OData-Version: 4.0

Response:

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal
OData-Version: 4.0

{
"@odata.context":"[Organization URI]/api/data/v9.2/$metadata#accounts(00000000-0000-0000-0000-000000000001)/name",
"value":"Adventure Works (sample)"
}

Retrieve the raw value of a property

To retrieve the raw value of a primitive property, rather than JSON, append /$value to the URL; for example:

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)/name/$value HTTP/1.1
Accept: application/json
OData-MaxVersion: 4.0
OData-Version: 4.0

Response:

HTTP/1.1 200 OK
Content-Type: text/plain
OData-Version: 4.0

Adventure Works (sample)

Using the raw value isn't common, unless you're working with file or image data. More information: Download a file in a single request using the Web API.

Retrieve navigation property values

You can access the values of navigation properties, or lookup fields, by appending the name of the navigation property to the URI of an individual entity.

The following example returns the fullname of the primary contact of an account using the primarycontactid single-valued navigation property:

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)/primarycontactid?$select=fullname HTTP/1.1
Accept: application/json
OData-MaxVersion: 4.0
OData-Version: 4.0

Response:

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal
OData-Version: 4.0

{  
"@odata.context": "[Organization URI]/api/data/v9.2/$metadata#contacts(fullname)/$entity",  
"@odata.etag": "W/\"500128\"",  
"fullname": "Rene Valdes (sample)",  
"contactid": "ff390c24-9c72-e511-80d4-00155d2a68d1"  
}

For collection-valued navigation properties, you can request to return only references to the related entities or just a count of the related entities.

The following example will return references to tasks related to a specific account by adding /$ref to the request.

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)/AccountTasks/$ref HTTP/1.1
Accept: application/json
OData-MaxVersion: 4.0
OData-Version: 4.0

Response:

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal
OData-Version: 4.0
  
{
    "@odata.context": "[Organization URI]/api/data/v9.2/$metadata#Collection($ref)",
    "value":
  [
    { "@odata.id": "[Organization URI]/api/data/v9.2/tasks(6b5941dd-d175-e511-80d4-00155d2a68d1)" },
    { "@odata.id": "[Organization URI]/api/data/v9.2/tasks(fcbb60ed-d175-e511-80d4-00155d2a68d1)" }
  ]
}

The following example returns the number of tasks related to a specific account using the Account_Tasks collection-valued navigation property with /$count appended:

Request:

GET [Organization URI]/api/data/v9.2/accounts(00000000-0000-0000-0000-000000000001)/Account_Tasks/$count HTTP/1.1  
Accept: application/json  
OData-MaxVersion: 4.0  
OData-Version: 4.0

Response:

2

Note

The value returned includes the UTF-8 byte order mark (BOM) characters (), which indicates that this is a UTF-8 document.

Use the $expand system query option to control what data from related entities is returned. More information: Join Tables

Detect if a record has changed since it was retrieved

As a performance best practice you should only request data that you need. If you've previously retrieved an entity record, you can use the ETag associated with a previously retrieved record to perform conditional retrievals on that record. More information: Conditional retrievals.

Retrieve formatted values

Request formatted values for individual record retrievals the same way you query entity sets.

See also

Perform operations using the Web API
Compose HTTP requests and handle errors
Query data using the Web API