Explanation
These two options are recommended ways to bring transactional data from a data warehouse into Data Cloud via a SFTP site. You can use the Cloud Storage Connector to ingest files from Google Cloud Storage or Amazon S3 buckets into Data Cloud. References:
https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_google_cloud_storage.htm&type=5https://he

According to the Data Cloud documentation, the Is Equal To operator is case-insensitive, meaning it matches values regardless of capitalization. Therefore, the segmentation criteria filtering on City | Is Equal To | 'San Jose' will include cities that contain either 'San Jose' or 'san jose'.

Explanation
The maximum limit of the number of records for Full Refresh Extract Method is 10 million. Full Refresh Extract Method is an option for extracting data from Marketing Cloud to Data Cloud. It extracts all records from a data extension regardless of when they were created or modified. If the number of records exceeds 10 million, an error occurs and no records are extracted. References: Extract Methods

One possible reason why a new custom field is not available in the data stream is that the Salesforce Integration User, which is used to connect to the CRM source, does not have "Read" permissions on that field2. To fix this issue, the administrator needs to grant the appropriate permissions to the Integration User profile or permission set.

Explanation
This permission set should be assigned to a user who needs permissions to access Data Cloud to create, manage, and publish segments, but not to create reports or manage data sources. This permission set allows the user to create and edit segments, calculated insights, streaming insights, and activations, but not to access data streams, data model, identity resolution, or reports.
References:https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_permission_sets.htm&type=5