Key Concepts: Revenue, Expenditure, and Production Cycles

Posted on Mar 22, 2025 in Criminological and Security Sciences

Key Concepts: Business Cycles

Revenue Cycle

  • Invoice: The most common output.
  • Employee & Delivery: Pick, Pack, Ship.
  • Purpose: Provide the right product, in the right place, at the right time, for the right price.
  • Invoice Methods: Balance forward and open invoice.

Expenditure Cycle

  • Purpose: Minimize the total cost of acquiring and maintaining inventories, supplies, and other necessary services.
  • Blanket PO vs. Vendor-Managed Inventory:
    • Blanket PO: Recurring purchases.
    • Vendor-Managed Inventory: Vendor manages inventory at your location.
  • 3-Way Matching: PO, Receiving Report, Invoice.
  • 2-Way Matching: Voucher System (compares PO to Receiving Report).
  • Main Activities: Ordering, Receiving, Approve Vendor Invoices, and Cash Disbursements.
  • Purchase Requisition vs. Purchase Order: Requisition is internal and not legally binding; an order is legally binding and external.

Production Cycle

  • Core ERD Example: Police Baton.
  • Purpose: Efficiently design, plan the production of, and manufacture products.
  • Bill of Material: Ingredients list.

General Business Cycle Concepts

  • Common Element: Product.
  • Cycle Identification:
    • Selling something? – Revenue Cycle.
    • Buying something? – Expenditure Cycle.
    • Making something? – Production Cycle.
  • Connect delivery out SQL and SO.

Cardinality & Relationships

  • Cardinality: The number of instances in a given entity that are associated with an instance in another given entity.
  • Degrees of Relationships: Unary, binary, ternary.
  • Entity Types: Attribute, Entity, and Record.
    • A record is a row in a table. It contains data related to a unique value.
    • An entity is a data object roughly analogous to a table.
    • An entity has attributes that become the fields in a table.
  • Attribute Types: Composite, Single-value, Multi-value, and Derived.
  • Key Donation Rule: If an entity has crows feet, it does not donate; otherwise, it donates.
  • 7 Rules: Nouns and Verbs, Weak Entities, Primary Keys, Mandatory Side, Many-to-many, Sub-Type Super-Type, No Data Duplication.

Subtype & Supertype

  • Overlap vs. Disjoint:
    • Disjoint: An individual of the parent class may be a member of only one specialized subclass.
    • Overlapping: An individual of the parent class may be a member of more than one of the specialized subclasses.
  • Subtypes inherit primary keys from supertypes.
  • The last attribute in the Super type is THING type.
  • Multi value is based on O or D.
  • Constraints: Generalization: total or partial specialization, Disjoints O or D.