The fieldType property specifies the category
of the values stored in the item.
Purpose
fieldType values:
TABLE_COLUMN: the value is defined in terms of a database
column. Provide the sqlTabName, the name
of the database table. Provide the colName, the
name of the database column.
NON_DATABASE: the value is not defined in terms of a database
column .
COLUMN_LIKE : the value is like NON_DATABASE, but takes
its description from a database column.
TABLE_ALIAS: the value is defined in terms of an alias
that is assigned to a database table.