A schema is the structure of the database that defines the objects in the database (Fig. 1a). A database schema of a database system is its structure described in a formal language supported by the database management system (DBMS). The term "schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases) (Fig. 1b). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database. These integrity constraints ensure compatibility between parts of the schema.
A databases generally stores its schema in a data dictionary. Although a schema is defined in text database language, the term is often used to refer to a graphical depiction of the database structure.
Figure 1a. - select image to enlarge
A section of the SBL Schema
Figure 1b. - select image to enlarge
Here on the left, the SBL schema is defining the attributes "socialSecurityNumber" and "birthDate" of the SBL import file on the right.
The purpose of an XML Schema is to define the legal building blocks of an XML document
- the elements and attributes that can appear in a document
- the number of (and order of) child elements
- data types for elements and attributes
- default and fixed values for elements and attributes
Looking for the Following?
Attributes Document (SBL Data Dictionary)
- Lists attributes that make up SBL.
- Provides a data definition for each field.
- Shows required fields.
- Identifies field restrictions, if there are any, including valid values.
- Shows schema field names.
- Lists SBL elements in the order they have to be specified.
- Shows parent/child relationships.
- Shows required fields.
- Identifies field restrictions, if there are any, including Value Lists for fields with a restricted list of valid values.
- Maps out the relationship between the SBL fields and the Database tables and fields.
- Can assist in building an SBL.xml file.