# Topics

## Data-tier applications (DAC)

* A data-tier application (DAC) is a logical database entity that defines all of the SQL Server objects - such as tables, views, and instance objects, including logins - associated with a user's database.&#x20;
* A DAC is a self-contained unit of the entire database model and is portable in an artifact known as a DAC package, or _.dacpac_ which can be deployed to new or existing databases.

## Table Hints

`NO_LOCK` - used to read the data that has been changed but not yet committed to the database.

## Views

The conceptual view is referred to as the total view of a database.

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