Here quasi means form seeming to be but not really so. Repository means a storage place. Here case tools are “structured analysis and design tool”
The notation enables a SE to represent composite data as a sequence of data items. Data dictionary defines information items un-ambiguously.
Control specification –represents the behaciour of system in 2 ways. That is, STD that is a sequencial specification of behaviour and a PAT.
What is a DATA DICTIONARY?
The Data Dictionary
a quasi-formal grammar for describing the content
of data that the software will process and create
a notation for describing control data and the
values that control data can take, e.g., "on," or "off"
a repository that also contains "where-used" / "how
a notation that can be represented manually, but is
best developed using CASE tools
Building a Data Dictionary
the primary name of the composite data item
other names for the data item
data transforms (processes) that use the
composite data item
the role of the data item (input, output,
temporary storage, etc.
a notation for representing content (presented
on next slide)
specific information about data types, pre-set
values (if known)
Data Dictionary Notation
( ... )
* ... text ...*
is composed of
n repetitions of
delimits a comment
Data Dictionary Example
phone number, number
telephone no. = [ local extension | outside no. | 0 ]
outside no. = 9 + [ service code | domestic no. ]
service code = [ 211 | 411 | 611 | 911 ]
domestic no. = ( ( 0 ) + area code ) + local number
area code = *three numeral designator*
Build the requirements dictionary:
Control Flow Model
CFD is a diagram to describe the control flow of a
business process, or program.
Begin by stripping all the data flow arrows from the
Events (solid arrows) and control items (dashed arrows)
are added to the diagram
Add a window to the CSPEC (contains and STD that is a
sequential specification of the behavior) for each