Promotion criteria is an SQL WHERE clause used to select which products are included.

All crisps
    PRODUCTS.NAME LIKE '%crisps%
   
Item with barcode 5098276743003
    PRODUCTS.CODE = '5098276743003'

All products in the wines category except champagne
    CATEGORIES.NAME = 'Wine' AND NOT PRODUCTS.NAME LIKE '%champagne%'

Field names are any from these database tables: PRODUCTS, CATEGORIES, TAXCATEGORIES
For example:
    PRODUCTS.ID            // Product ID
    PRODUCTS.REFERENCE     // Product Reference
    PRODUCTS.CODE          // Product bar code
    PRODUCTS.NAME          // Product Name
    CATEGORIES.NAME        // Category Name
    TAXCATEGORIES.NAME     // Tax category Name

