Release 10.1A: OpenEdge Development:
Programming Interfaces

Representing temp-tables in XML Schema

Temp-tables are represented with an XML Schema element definition, followed by a complex type definition defining the fields. The XML Schema name attribute identifies the name of the temp-table. The following Progress-specific XML Schema attributes further describe the temp-table:

undo — identifies the temp-table as UNDO
beforeTable — specifies the name of any before-image table for this temp-table
bufferName — If the XML Schema is written for a non-default buffer of a temp-table, this attribute specifies the buffer name.

Temp-table fields can be represented as elements, attributes or text in an XML Document. The XML-NODE-TYPE attribute on the buffer-field object lets you control how fields are represented in the XML document and the XML Schema.

XML Schema provides the following built-in attributes for minimally describing a temp-table field in an element definition (when the buffer-field has an XML-NODE-TYPE of "ELEMENT"):

name — name of the field.
type — data type of the field.
minOccurs/maxOccurs — extent of array fields.
nillable — can be null or unknown (always has a value of "true" for temp-table fields). Unknown fields have xsi:nil attribute set to "true" in the XML instance.
default — the initial value for the field. If the field has the default initial value for it's data type (for example, 0 for integer), the attribute will not be present in the XML Schema.

XML Schema provides the following attributes for attribute definitions (when the buffer-field has a XML-NODE-TYPE of "ATTRIBUTE"):

name — name of the field
type — data type of the field
default — the initial value for the field. If the field has the default initial value for it's data type (for example, 0 for integer), the attribute will not be present in the XML Schema.

XML Schema provides the following attribute for simple content definitions (when the Buffer-field has a XML-NODE-TYPE of "TEXT"):

type — data type of the field.
Notes: If you want to be able to explicitly set a field to the Unknown value (?) (xsi:nil="true"), it must have XML-NODE-TYPE = "ELEMENT"

Array fields must have XML-NODE-TYPE = "ELEMENT" or "HIDDEN"

Buffer fields with XML-NODE-TYPE="TEXT" cannot be part of a nested DATA-RELATION.

Progress provides the following XML Schema extensions for describing Progress-specific attributes of a temp-table field. These attributes, with the exception of dataType and initial, will only appear in the XML Schema when the min-xmlschema option for WRITE-XML() method or WRITE-XMLSCHEMA() method is FALSE.

Table 22–8: Progress XML Schema extensions for temp-table fields

XML Schema attribute	Description
caseSensitive	Case-sensitive for CHARACTER fields
columnCodepage	Column-codepage for CLOB fields
columnLabel	Column-label for the field
dataType	The Progress data type for fields where the XML Schema type attribute maps to multiple Progress data types (for example, string, base64Binary, dateTime). See Appendix D "XML Reference of Data Type and Code Page mappings."
decimals	Number of decimal places for DECIMAL fields
format	Display format for the field
fieldName	Name of the field. Used only for fields with XML-NODE-TYPE of "TEXT"
help	Help text for the field
initial	Initial value for the field. Used for fields with XML-NODE-TYPE of "TEXT", and for fields with initial value of TODAY, NOW or UNKNOWN.
label	Label for the field
readOnly	Read-only attribute for the field
userOrder	Position of the field in the temp-table. This attribute is used only when there's a mix of fields with XML-NODE-TYPE of "ELEMENT" and "ATTRIBUTE" in the temp-table.

Note: If any of the above Progress-specific field attributes have the Progress default value, WRITE-XML() method and WRITE-XMLSCHEMA() method will omit the attribute from the element or attribute definition when it writes the XML Schema.