ERWin Template Overview
By: Dave Wentzel
Agenda
 Overview
of Templates/Macros
 Template editor
 Available templates
 Independent column browser
 Forward engineering process
 Trouble shooting
What is a template ?
 ERWin
contains a macro language
 Used for the creation of:
– Stored Procedure Templates
– Trigger Templates
– Table script template (pre & post)
 Based
on type of template, will
automatically generate SP, trigger, or script
based on table/relationship information
when the model is forward engineered
Why are we using templates?
 Provide
turn-key approach to data model
creation
 Reduce the number of triggers and stored
procedures which need to be written
 Can more easily make model changes
without having to ‘re-write’ triggers and
SPs
A little on the Macro Language...
 ERWin
contains a Template Toolbox which
is used to create the templates
Types of Macros
 Entity
– Applied to tables in the diagram
– Can be used to act as a loop - ‘For Each Entity’
– Can be used to reference qualities of an entity ‘For Each (Attribute/Index/Key…)’
 Relationship
– Applied to relationship information between
entities
– Can reference PK, FK, Parent/Child entities
Types of Macros Continued
 Attribute
– References ‘attributes’ of attributes such as
length, field type, FK/PK, etc.
 Constraint
– References database constraint information
 Miscellaneous
– Arithmetic operators
– Comparison operators
– System Information
Stored Procedure Templates
 Generates
a stored procedure for WRITING
/ UPDATING a record in a table
 Based on primary key attributes
 If the key values are equal to an existing
record, the record will be updated
 If no matching record is found, a new
record will be inserted
 To be used as low level write routine called
from higher level SPs.
Accessing the SP Templates
 Right
mouse click on a table
 Select Table Editor / Stored Procedure
option
 Attach the appropriate template to the table
 One must be attached for each table
Available Templates
 Write
Template
 Stand Alone Table Triggers
 Write Dimension Template
 Write Fact Template
Write Template
 Creates
spWriteTableName
 Assumes PK is an IDENTITY column
 Assumes PK is FieldNameInst
 Assumes columns:
– Create Date / Create User
– Modify Date / Modify User
– If PK provided, updates record otherwise inserts new
record
Standalone Table Triggers
 Generates
the insert/update triggers for
standalone tables
 Standalone tables may occur if created as a
reference table
 Generated through the SP template instead
of the Trigger template because the trigger
template assumed relationships
Write Dimension Template
 Found
in Datamart diagrams
 Assumes a PK of identity
 Assumes PK is FieldNameInst
 Assumes no updates
 If PK does not exist, will write new record
Write Fact Template
 Found

in Datamart diagrams
Inserts new records into fact tables
Trigger Templates
 Generates
Update/Delete/Insert triggers for
a table and it associated tables
 Helps maintain RI and date validations
between related tables
Triggers and Relationships
 Triggers
are generated based on
relationships between two entities
 Double click on a relationship line
– Child Delete / Insert / Update
– Parent Delete / Insert / Update
 Options:
– Restrict - prevent
– Cascade - propagate change
– None - no trigger relationship
Accessing the Trigger Templates
 Left
mouse click on a table
 Select SQL Server Trigger
 Select SQL Server Trigger Template to attach
Triggers
Available Trigger Templates
 Approach
Child Delete Restrict
 Approach Child Delete Cascade
 Approach Child Insert Restrict
 Approach Child Update Restrict
 Approach Parent Delete Cascade
 Approach Parent Delete Restrict
 Approach Parent Insert Restrict
 Approach Parent Update Restrict
Available Trigger Templates
 Approach
Delete Footer
 Approach Delete Header
 Approach Insert Footer
 Approach Insert Header
 Approach Update Footer
 Approach Update Header
Parent / Child Templates
 On
restrict, provides Raise Error message when a
parent / child relationship exists
 On cascade, will delete all associated tables with
the same primary key
 Verifies records do not overlap based on from and
thru dates
 Requires fields either FromDate / ThruDate or
BeginDate / EndDate
 Assumes domain type of ID in some models
Header / Footer Templates
 Header
creates the ‘Create Trigger’ code,
parameters, and initial date checks against
the table
 Footer templates update the
ModifyDate/User in the update triggers
 Assume ModifyDate/ ModifyUser fields
Standard selections for RI Actions
Table Templates
 Pre
/ post scripts generated during table
creation
 Used to generate print statement before
table creation so implementation script is
easier to read
 Used for the OLAP fact tables to generate
update triggers
Accessing Table Templates
 Left
click on table
 Select Table Editor / Pre & Post Script
Independent Column Browser
 Provides
method of creating standard fields
for use in current data model
 Example: Used for standard fields applied
to all tables
 Domain type of ID exists which is
referenced by some templates and must be
assigned PK identity columns
Accessing the Independent
Column Browser
 Under Window
select Independent Column
Browser Option
Forward Engineering the Model
 Triggers,
stored procedures, and table
scripts will be generated when you forward
engineer the data model - based on the
options you select
 To forward engineer the model, select:
Tasks \ Forward Engineer/Schema
Generation
Schema Generation
Schema Options to Select
 Table
–
–
–
–
–
–
Create Table
Drop Table
Pre-Script
Post-Script
Create Procedure
Drop Procedure
Options continued
 Column
– Validation
– Default
 Index
– Create Index
» Alternate Key
» Foreign Key
» Inversion Entry
» CLUSTERED
» Physical Storage
Options Continued
 Referential
Integrity
– Primary Key
» Alter (PK)
– Foreign Key
» Alter (FK)
 Trigger
– User Defined
» RI Type Override
» Relationship Override
Forward Engineer
 Select
PREVIEW
 Cut / paste into SQL query window to run
 Do not directly forward engineer into the
database
– Could delete items you did not anticipate
– May be connected to a production server
Troubleshooting
 Execute
script
 Review error statements
 Review script code with error
 Access the template to see what it is
expecting
 Verify correct relationships, triggers, SPs,
etc. are associated with the table
 Verify required fields are assigned to the
table