Entity Data Model
The Entity data model (EDM) specifies the conceptual model (CSDL) of the data via the Entity-Relationship model, which deals primarily with Entities and the Associations they participate in. The EDM schema is expressed in the Schema Definition Language (SDL), which is an application of XML. In addition, the mapping (MSL) of the elements of the conceptual schema (CSDL) to the storage schema (SSDL) must also be specified. The mapping specification is also expressed in XML.
Visual Studio also provides Entity Designer, for visual creation of the EDM and the mapping specification. The output of the tool is the XML file (*.edmx) specifying the schema and the mapping. Edmx file contains EF metadata artifacts (CSDL/MSL/SSDL content). These 3 files (csdl, msl, ssdl) can also be created or edited by hand.
Read more about this topic: ADO.NET Entity Framework
Famous quotes containing the words entity, data and/or model:
“What is this world of ours? A complex entity subject to sudden changes which all indicate a tendency to destruction; a swift succession of beings which follow one another, assert themselves and disappear; a fleeting symmetry; a momentary order.”
—Denis Diderot (1713–1784)
“Mental health data from the 1950’s on middle-aged women showed them to be a particularly distressed group, vulnerable to depression and feelings of uselessness. This isn’t surprising. If society tells you that your main role is to be attractive to men and you are getting crow’s feet, and to be a mother to children and yours are leaving home, no wonder you are distressed.”
—Grace Baruch (20th century)
“I had a wonderful job. I worked for a big model agency in Manhattan.... When I got on the subway to go to work, it was like traveling into another world. Oh, the shops were beautiful, we had Bergdorf’s, Bendel’s, Bonwit’s, DePinna. The women wore hats and gloves. Another world. At home, it was cooking, cleaning, taking care of the kids, going to PTA, Girl Scouts. But when I got into the office, everything was different, I was different.”
—Estelle Shuster (b. c. 1923)