Custom field data space in each part is implemented as a separate table with columns, corresponding to custom fields.
In order to ensure maximum interoperability and compatibility with a wide range of database-to-database or database-to-middle tier integration cases, UnifieidLogon restricts custom fields to the following lowest common denominator base data types:
- Character - implemented as varchar 1...254 characters long
- Numeric - implemented as integer or numeric with optional decimal places, maximum 15 digits
- Text - large text up to 2 GB
Data type change is permitted in the following safe conversions cases:
- Increasing datatype width (character to character, numeric to numeric, character to text)
- Safe casting (boolean to numeric or character or text, numeric to character or text, datetime to character or text)
"Lucky" conversion might also be possible if data with original data type is still compatible with new data type (text to character, text or character to numeric, character or text to boolean, character or text to datetime).
In all other cases, data loss is possible, and database level data manipulation is advised prior to changing data types.