Dynamic Selects Columns Settings: An Introduction
As previously noted, in the case of a Dynamic Selects field (FieldtypeDynamicSelects, i.e. for backend use) each dropdown has a corresponding and exactly named column in the database table of your Dynamic Selects field.
To add a column, click on the add column link as shown in the image above. This will create a new row in the columns settings HTML table.
The columns settings HTML table (above image) has 7 HTML table columns (+, Name, Label, Trigger, Relationship, Data Source, Trash Can). Each of these is described in more detail in the next topics. Please note that the HTML table columns are mainly used to define the dynamism between your dropdowns. Each row in this HTML table corresponds to ONE dropdown (and hence ONE of the database table columns in the case of a Dynamic Selects field). This is very important to understand and is illustrated in the following image.
In summary, in the columns settings HTML table, you define the names of your dropdowns as well as their labels. In the case of backend use, each name will correspond to a column name in your field's database table. In that case, each column will be used to store the selected data from the corresponding dropdown. Even more important, in the HTML table, you also define the triggers, relationships and data sources for and between your dynamic dropdowns.
Each input required in defining columns settings is described in more detail in the next topics.