Group items tagged

XSDDataTypes Package: This package contains classes representing XSD primitive data types. This package is available as an XMI file. To import the file as a UML Package, use EA's XMI import facility which is available from the menu item: Project | Import/Export | Import Package from XMI. UML Profile for XML: This resource file contains the stereotyped classes which allow the schema generation to be customized. The UML Profile for XML can be imported into a model using the Resource View (see Importing Profiles for details on importing UML profiles into EA).

Steps to Generate XSD: Select the package to be converted to XSD by right-clicking on the package in the Project Browser. Select Project | Generate XML Schema from the main menu. Set the desired output file using the Filename field. Set the desired xml encoding using the Encoding field. Click on the Generate button to generate the schema. The progress of the schema generator will be shown in the Progress edit box.

user == schema owner == named account

In PostgreSQL:

server instance == db cluster

database == catalog == single database

identify the

catalog

In an EAV data model, each attribute-value pair is a fact describing an entity, and a row in an EAV table stores a single fact

EAV tables are often described as "long and skinny": "long" refers to the number of rows, "skinny" to the few columns

Data is recorded as three columns: The entity: the item being described. The attribute or parameter: a foreign key into a table of attribute definitions. At the very least, the attribute definitions table would contain the following columns: an attribute ID, attribute name, description, data type, and columns assisting input validation

The value of the attribute

Row modeling, where facts about something (in this case, a sales transaction) are recorded as multiple rows rather than multiple columns

differences between row modeling and EAV (which may be considered a generalization of row-modeling) are:

A row-modeled table is homogeneous in the facts that it describes

The data type of the value column/s in a row-modeled table is pre-determined by the nature of the facts it records. By contrast, in an EAV table, the conceptual data type of a value in a particular row depend on the attribute in that row

In the EAV table itself, this is just an attribute ID, a foreign key into an Attribute Definitions table

The Attribute

The Value

Coercing all values into strings

larger systems use separate EAV tables for each data type (including binary large objects, "BLOBS"), with the metadata for a given attribute identifying the EAV table in which its data will be stored

Where an EAV system is implemented through RDF, the RDF Schema language may conveniently be used to express such metadata

access to metadata must be restricted, and an audit trail of accesses and changes put into place to deal with situations where multiple individuals have metadata access

quality of the annotation and documentation within the metadata (i.e., the narrative/explanatory text in the descriptive columns of the metadata sub-schema) must be much higher, in order to facilitate understanding by various members of the development team.

Attribute metadata

Validation metadata include data type, range of permissible values or membership in a set of values, regular expression match, default value, and whether the value is permitted to be null

Presentation metadata: how the attribute is to be displayed to the user

Grouping metadata: Attributes are typically presented as part of a higher-order group, e.g., a specialty-specific form. Grouping metadata includes information such as the order in which attributes are presented

Advanced validation metadata Dependency metadata:

Most of the important information is really stored in the edges

names

addresses

checking similar products!

return a row

3 ways to do this

EntityManger.find()

returns a typed instance of the entity when it is found, null when it is not found

But what if the row isn’t in the database (anymore)?

We get an unchecked exception: NoResultException

We never know for sure what we can expect from our database, so throwing an unchecked exception seems the wrong choice for this use-case

Tutorials All Tutorials UML Tutorials UML 2.1 Tutorial UML Tutorial - Part 1 Intro UML Tutorial - Part 2 Intro The Business Process Model The Component Model The Dynamic Model The Logical Model The Physical Model The Use Case Model UML Database Modeling Enterprise Architect Tutorials Creating Strategic Models Diagram Filters BPEL: Step by Step Guide Resource Management Testing Management Traceability RTF Documentation Use Case Metrics Structured Use Case Scenarios

Video Demonstrations All Videos Getting Started Requirements Management Modeling & Productivity Tools Code Engineering and the Debug Workbench Version Control Integration (Eclipse, Visual Studio, TFS)

UML Tutorial - Structure UML Tutorial - Behavior The Business Process Model Deployment of EA MDA Overview Rich-Text (RTF) Reporting Version Control Integration Requirements Management

White Papers & E-Books

Roles Business Analyst Database Administrator Deployment & Rollout Developer Project Manager Software Architects Software Engineer Technology Developer Testers

Solutions

MDG Technologies MDG Technologies EJB Technology.xml Testing Technology.xml

UML Profiles & Patterns UML Patterns UML Patterns Create UML Patterns Import UML Patterns Use UML Patterns UML Profiles UML Profiles: Introduction UML Profile for SPEM XML Schema (XSD) Generation Web Modeling Profile Eriksson-Penker Business Extensions Open Distributed Processing (UML4ODP)