What is the data access module? (arcpy.da)

The data access module, arcpy.da, is a Python module for working with data. It allows control of the edit session, edit operation, improved cursor support (including faster performance), functions for converting tables and feature classes to and from NumPy arrays, and support for versioning, replicas, domains, and subtypes workflows.

Data Access functions

Class	Description
ExtendTable	Joins the contents of a NumPy structured array to a table based on a common attribute field. The input table is updated to contain the fields from the join table.
FeatureClassToNumPyArray	Converts a feature class to NumPy structured array.
ListDomains	Lists the attribute domains belonging to a geodatabase.
ListReplicas	Lists the replicas in the workspace.
ListSubtypes	Returns a dictionary of the subtypes for a table or feature class.
ListVersions	Lists the versions in the workspace.
NumPyArrayToFeatureClass	Converts a NumPy structured array to a point feature class.
NumPyArrayToTable	Converts a NumPy structured array to a table.
TableToNumPyArray	Converts a table to NumPy structured array.
Walk	Generate data names in a catalog tree by walking the tree top-down or bottom-up. Each directory/workspace in the tree yields a tuple of three: dirpath, dirnames, and filenames.

Data Access classes

Class	Description
Domain	The Domain object contains properties that describe an attribute domain.
Editor	The Editor class allows use of edit sessions and operations to manage database transactions.
InsertCursor	InsertCursor establishes a write cursor on a feature class or table. InsertCursor can be used to add new rows.
Replica	The Replica object contains properties that describe a replica.
SearchCursor	SearchCursor establishes read-only access to the records returned from a feature class or table.
UpdateCursor	UpdateCursor establishes read-write access to records returned from a feature class or table.
Version	The Version object contains properties that describe a version.

Nota:

The Walk function was made available at ArcGIS 10.1 Service Pack 1.