1.1.4 NVarChar

NVarChar is a variable-length character field, with a maximum length between 1 and 65,535. (This is the number of characters, not the byte length.)

NVarChars store alpha data of any codepage. For example, in a list, an NVarChar field may have Japanese in one row, and French in another row.

NVarChars are classified as unicode strings.

An NVarChar retains any trailing blanks, they are significant. When concatenating an NVarChar with spaces on the end, those spaces are retained. But the space is NOT SIGNIFICANT for comparisons.

Please review the general 1.1.1 Field Type Considerations.

Field Definition Rules

Rules for defining an NVarChar field in the repository are:


NVarChars may be 1 to 65,535 in length. NVarChars have no decimals.

Valid Keyboard Shift


Allowed Attributes


Edit Mask

NVarChars may be used for lookup predermined joined fields.



Usage Rules

Partition Type

RDMLX Enabled Partition


NVarChars may only be used in RDMLX Files. NVarChars may be used as real or key fields. If used as keys, length must be no more than 2000 characters.

Logical Views

NVarChars may be used as key fields. If used as keys, length must be less than 2000 characters.

Virtual Fields

NVarChars may be used with Code Fragment Virtual Fields.

Predetermined Join Fields

NVarChars may be used for lookup predermined joined fields.

RDML Commands

DEF_FOOT, DEF_BREAK, and DEF_LINE only support printing of RDML fields. Therefore, NVarChar fields need to be converted to Alpha to be used in reports.

Built-In Functions

When used in Built-In Functions, NVarChars are valid for arguments of type 'A'.

Special Values



Refer to Field Type Conversions.

Usage Notes

     So, be aware that your application cannot make a distinction between an empty NVarChar and a NVarChar with 1 blank. Also, concatenations of a zero length NVarChar before inserting to the database and after reading may differ by the extra space. Behaviour can be made consistent by truncating trailing spaces before using NVarChars in an expression. Note that when comparing an empty NVarChar in RDML to an NVarChar with 1 space read from the database they will compare equal because trailing spaces are not significant in comparisons - they are only significant in expressions, like concatenation.

Platform Considerations

Tips & Techniques

Also See

1.1.2 Alpha

1.1.3 String