The purpose is to allow definition of domains.
 

Properties
Name
Description
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Data type

Depending on the data type value, different properties are displayed:
 

Blob data type
FileType
Enum values
Character data type
Length
Enum values
Dimensions
Picture
    Case
Date data type
Enum values
Dimensions
Picture
    Date format
Datetime data type
Enum values
Dimensions
Picture
    Date format
    Hour format
Varchar and Long Varchar data type
Maximum length
Average length
Enum values
Dimensions
Picture
    Case
Numeric data type
Autonumber
Length
Decimals
Signed
Enum values
Dimensions
Picture
    Left fill
    Thousand separator
    Prefix

More details

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