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External data viewable in Salesforce in real-time without copying data into Salesforce
Data is formatted into Salesforce Objects
No storage is consumed in your org
Read only and read/write
You can search the data through standard salesforce search
You can use Apex and SOQL queries on the data.
The data is stored “by reference”
Transmissions through the Salesforce Connect service are already encrypted using mTLS.
The external system can be another Salesforce Org - you can connect to 5 other orgs with 1 (expensive) Connect licence.
You can write your own Custom Adaptor if not using a pre-built OData connector - it’s pretty cool
On the external data source, the Identity Type field specifies whether your organization uses one set or multiple sets of credentials to access the external system. Each set of credentials corresponds to a login account on the external system.
set up your OData producer to receive gzip-compressed data.
20,000 OData callouts per hour for Enterprise, Performance, and Unlimited editions. Higher limits are available on request.
You can have high data volume limits
The following features aren’t available for external objects that are associated with high-data-volume external data sources.
Access via Lightning Experience (WHAT?!)
Access via the Salesforce mobile app (AGAIN, WHAT?!)
Appearance in Recent Items lists
Record feeds
Reports and dashboards (Why would you use this then?)
Writable external objects
CSRF protection isn’t available for high-data-volume external data sources.
In addition to enabling CSRF protection on the external data source, we recommend keeping CSRF protection enabled in your org’s session security settings. These session settings are enabled by default, and keeping them enabled protects your Salesforce data and your external data from CSRF attacks
Use InsertAsync command in Apex to write to external data. https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_connector_external_objects_writeable.htm
The Lightning platform can’t save changes to an external object and a standard or custom object within the same transaction.
When users create, update, or delete external object records via the user interface, the operations occur synchronously.
When processes or flows create, update, or delete external object records, the operations occur synchronously.