DoD EA Dip Cse - Data Modelling in SA Block 12 May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA See the SA help file, on the Search tab enter in Data Modeling, sort the list by title and then go to the section called ‘Data Modeling’, the SA Quick Start entry. Read thru the section displayed for a good overview of data modeling functionality in SA. ER Diagrams – do these first. ER diagrams ER diagram properties ie right click on the back ground of the diagram to access this. This series of slides provides reminders about how to do data modelling in System Architect. Start with ER diagrams Note: Subject Area diagrams represent a portion of a model or system Note: the diagram type can be as a Model or a Subject Area May 2006 DoD EA Dip Cse - Data Modelling in SA

Project Data Models, Models and Subject Areas What is a Model/Project Model or Subject Area diagram? A Project Model is only a definition and it contains zero or one Model diagrams and zero, one or many Subject Area diagrams. A Subject Area diagram represents a portion of a model or project model. It can share entities and relation lines, or the user can define an entity for use within only a single subject area diagram A Model diagram is a pictorial representation of the entire system.  It includes all entities, attributes, access paths, and relationships that have been defined as belonging to the project model. For help on project models etc see the SA help file. Use the Index tab and enter in ‘Project Data Model’. Note: To build a Conceptual Data Model in System Architect, you would use an ER diagram, and use the Non-specific relation line to model relationships between entities May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA Project Data Model Model Subject Area May 2006 DoD EA Dip Cse - Data Modelling in SA

Data Entities, Data Elements and Attributes An ‘Entity’ has ‘Attributes’, each attribute is based on a ‘Data Element’. This is the ‘Data’ column. The particular instance of a ‘Data Element’ as an ‘Attribute’ for this ‘Entity’ can have a different name. This is entered in the ‘Name’ column of the ‘Attribute List’. Once created you get an Attribute definition as well as the Data Element definition as shown on this slide. You will see these different definition records listed in the Browser. Once you change the name column value you need to click the Apply button before SA creates the newly named instances of the attribute. Once you change the name column value you need to click the Apply button before SA creates the newly named instances of the attribute. May 2006 DoD EA Dip Cse - Data Modelling in SA

Data Structure Definitions ‘Data Elements’ can be grouped to create ‘Data Structures’. The ‘Data Structures’ can then be used in the ‘Attribute List’ as well. May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA Attribute Definition ‘Attributes’ are instances of ‘Data Elements’ that are used in ‘Entities’. In the ‘Browser’ an ‘Attribute’ is displayed followed by the ‘Model’ and ‘Entity’ of which it is a part. When entering Attribute entries in the Entity Definitions grid you will need to click apply to make the name changes be written to the database. Remember to use the ‘Update FKs’ or ‘Remove FKs’ function on the ‘Dictionary’ menu after you create relationships. Error and Normal Form check reports are available on the ‘Reports’ menu once you have a Data Model diagram open. Note: Data Structures can also be used but ensure you have selected to use data structures by selecting "Struct as Entity data choice" in the System Architect Property Configuration dialogue. May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA ER Diagram Example This is an example of an Identifying Relation. Because of the ‘Supervises’ relation the staffname data element had to have ‘Supervisor’ added as a role in the attribute grid.. This is an example of a Non Identifying Relation. These are an example of the super - sub Relation. Note: SA automatically adds the dash box. May 2006 DoD EA Dip Cse - Data Modelling in SA

Data Modelling Utilities In SA help go to the Search tab and enter in "column name options“ and read the section on using. Foreign keys are computed and created by System Architect, you cannot toggle on the FK (Foreign Key) checkbox for attributes of an entity, you can only toggle on/off the PK (Primary Key) checkbox. Use the Update or Remove Fk’s to cause SA to walk the currently open data model, and create Foreign Keys as necessary (or remove them where necessary) depending on the primary keys of entities and the relationships between entities. May 2006 DoD EA Dip Cse - Data Modelling in SA

Generate and OV7 or SV11 from your ER Diagram New OV7 diagram is created. This is a logical data model and uses the IDEF1x notation. Note: the notation for relationship lines can be changed to suit your preference. See the the Format menu  Diagram Format  Notation for the choices. This is the dialogue for generation of the SV-11. Note in the SA help file Physical Data Model is abbreviated to PDM. May 2006 DoD EA Dip Cse - Data Modelling in SA

SV-11 Physical Data Model (PDM) SA prompts you for the DBMS type and Database Name. Report of the results of running the Create SV-11… utility. New SV-11 entry in the Browser. Note: this is now a ‘Table’ instead of an ‘Entity’. Note: this is now a ‘Table’ instead of an ‘Entity’. May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA This is the ‘Model’ In SA an attribute is identified by the model and entity to which is belongs. An Attribute is of a type of Data Element. May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA Data Objects – OV6 The OV6 BPMN diagram type has symbols representing data objects. A data object is a collection of data entities. A ‘Data Object’ modelled in an OV6 (BPMN) represents one or more ‘Entity’ records. May 2006 DoD EA Dip Cse - Data Modelling in SA

Dictionary Update – Helps improve data integrity May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA This is an example of a Dictionary Update report. One error was found. May 2006 DoD EA Dip Cse - Data Modelling in SA

DoD EA Dip Cse - Data Modelling in SA SA also provides a range of reports to help with data modelling. These are not shown until a data model diagram is open. The Balancing reports are for Data Flow diagrams (DFD’s) ie SV4’s. But the Normal form reports can also be run for ER or OV7/SV11 diagrams as well. Result of running the 2nd & 3rd Normal Form utility. Error log is shown and symbols with errors is shown on the diagram. Remove these with the ‘Clear Errors’ option. Result of running the 2nd & 3rd Normal Form utilitiy. Error log is shown and symbols with errors is shown on the diagram. Remove these with the ‘Clear Errors’ option. Result of running the 2nd & 3rd Normal Form utilitiy. Error log is shown and symbols with errors is shown on the diagram. Remove these with the ‘Clear Errors’ option. May 2006 DoD EA Dip Cse - Data Modelling in SA