22.9.2.19 ST_Xstring

String of characters with support for escaped invalid-XML characters.

For all characters which cannot be represented in XML as defined by the XML 1.0 specification, the characters are escaped using the Unicode numerical character representation escape character format xHHHH, where H represents a hexadecimal character in the character’s value. [Example: The Unicode character 8 is not permitted in an XML 1.0 document, so it must be escaped as x0008. end example]

This simple type’s contents are a restriction of the W3C XML Schema string datatype.

[Note: The W3C XML Schema definition of this simple type’s content model (ST_Xstring) is located in A.6.9. end note]