Extract Column References From The Miscellaneous Fields

The miscellaneous fields illustrated above require the following column references (we describe the referenced algorithms at the bottom of the table):

There are three types of algorithms referenced in the above table:

• Retrieval algorithm. A column's retrieval algorithm retrieves the column's current value from the database. You'll notice that only one of our columns uses a retrieval algorithm. This is because we've used a sophisticated example of a group of columns that are retrieved at the same time. When you have such a group of columns, nominate one of the columns to do the retrieval work and specify the retrieval algorithm on it.
• Validation algorithm. A column's validation algorithm validates the column's value prior to the database being updated. You'll notice that only one of our columns uses a validation algorithm. This is because we've used a sophisticated example of a group of columns that are validated as a group. When you have such a group of columns, nominate one of the columns to do the validation work and specify the validation algorithm on it.
• Post algorithm. A column's post algorithm updates the column's value on the database when the order is completed. You'll notice that only one of our columns uses a post algorithm. This is because we've used a sophisticated example of a group of columns that are posted together. When you have such a group of columns, nominate one of the columns to do the posting work and specify the posting algorithm on it.

Notice that we have indicated that one of the columns has a "foreign key reference". You declare a "foreign key reference" if the valid values for a column are defined on another table in the system (this also affects the order user interface as a dropdown appears for columns that have foreign key references). In our example, Auto Pay Source is the only column whose valid values are defined on the automatic payment source control table.