How to interpret term cardinality?
An SRS document is provided describing various aspects of the end-product, system maintenance tool. The only paragraph I'm failing to understand is "Component Cardinality". What does this term mean in such c开发者_运维百科ontext?
The table looks like this:
Component Cardinality
=========================
Trigger | 1..* | 1..*
Input | 1..1 | 1..*
Transform | 1..* | 1..1
And the other one:
Component | Configuration | Cardinality
=======================================
Trigger | Schedule | 1
| Recurrence | 1
| Condition | 0..*
Please help to interpret this properly. Many thanks
Cardinality typically refers to relationships and how many of a specific entity relate to another entity. The two tables might refer to input / output.
For example:
Component | Inputs | Outputs
----------------------------
Trigger | 1-1 | 1-*
----------------------------
Input | 1-1 | 1-*
----------------------------
Transform | 1-* | 1-1
Each of those indicating a 1-1 (One entity to One entity relationship), 1-* (One entity to many entities relationship).
The second chart seems to specific more details regarding a single component and indicating possible "types of Triggers. Perhaps that a single Schedule Trigger will be present (By cardinality 1), as will a single Recurrence Trigger (Also cardinality 1), and that 0-N Condition Triggers may be present in the system (From 0-* cardinality).
This is rather a shot in the dark but I hope it might help some.
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