Since I have now got a connection from UniVerse to MySQL, I have been giving some thought to how to implement multi-values within MySQL and get the same results as in the U2 products.

I eventually categorized the types of multi-valued field usage into the following:

  • Multi-valued Fields
  • Associated Fields
  • Lists
  • Complex Fields
  • Tables

Multi-valued Fields

This is the most common usage where the data within a field can have multiple values. Each value is the same data type e.g. date or integer.

Associated Fields

A number of fields, which are also multi-valued, are linked or associated together. Normally used to store data details instead of creating a separate file for storing related data to a main or master data file.

Lists

A list can be either a field of multi-values or a record of multi-fields.

Complex Fields

A field can hold multiple data values which are related but not of the same data type. An example is international date and time which consists of date, time and a time zone. These three pieces of data would be stored together within the same field as separate values.

Tables

A table can be 2 or 3 dimensional and stored using multi-values and multi-subvalues.

Subvalues are an interesting nominally within UniVerse; they have limited support within UniQuery and no support within SB+.