Oracle XMLELEMENT Example


XMLElement takes an element name for identifier, an optional collection of attributes for the element, and arguments that make up the content of the element. It returns an instance of type XMLType. XMLElement is similar to SYS_XMLGen except that XMLElement can include attributes in the XML returned, but it does not accept formatting using the XMLFormat object.

The XMLElement function is typically nested to produce an XML document with a nested structure, as in the example in the following section.

You must specify a value for identifier, which Oracle Database uses as the enclosing tag. The identifier can be up to 4000 characters and does not have to be a column name or column reference. It cannot be an expression or null.

The objects that make up the element content follow the XMLATTRIBUTES keyword. In the XML_attributes_clause, if the value_expr is null, then no attribute is created for that value expression. The type of value_expr cannot be an object type or collection. If you specify an alias for value_expr using the AS clause, the c_alias can be up to 4000 characters.

For the optional value_expr that follows the XML_attributes_clause in the diagram:

If value_expr is a scalar expression, then you can omit the AS clause, and Oracle uses the column name as the element name.

If value_expr is an object type or collection, then the AS clause is mandatory, and Oracle uses the specified c_alias as the enclosing tag.

If value_expr is null, then no element is created for that value expression.

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