To define an XDD file requires defining the data type of each column of the original data file. The following table describes the accepted XDD data types:
Type to be used in the XDD field specification |
Type description |
---|---|
NumUnsigned |
ASCII string representing an unsigned number |
NumSignSep |
ASCII string representing a signed number with trailing separate sign. |
NumSigned |
ASCII string representing a signed number with trailing sign |
NumSepLead |
ASCII string representing a signed number with leading separate sign |
NumLeading |
ASCII string representing a signed number with leading sign |
Alphanum |
ASCII string |
Float |
Float or Double values |
CompSigned |
Signed computational |
CompUnsigned |
Unsigned computational |
PackedPositive |
Packed string representing a positive number |
PackedSigned |
Packed string representing a signed number |
PackedUnsigned |
Packed string representing an Unsigned number |
BinarySigned |
Integer number represented in binary signed format (big endian) |
BinaryUnsigned |
Integer number represented in binary unsigned format (big endian) |
NativeSigned |
Integer number represented in native O/S binary signed format |
NativeUnsigned |
Integer number represented in native O/S binary unsigned format |
See also <schema> table element.
Variable length fields map into SQL LONGVAR* fields.
The XDD structure allows the following elements and attributes for variable length field support.
For an XDD field mapped into a LONG VARCHAR or LONG VARBINARY, the following conditions must be met:
size="0"
sizefield="X" where "X" is a valid field containing the number of bytes (we suggest this field to be hidden, but this is not mandatory)
dbtype="clob" or dbtype="blob"
If one (or more) of the above condition is not met, error CTDBRET_CALLBACK_11 ("Unsupported clob/blob definition") is returned.