What is XMLTABLE in Oracle?
Oracle 10g Release 2 introduced the XMLTABLE operator, which allows you to project columns on to XML data in an XMLTYPE , making it possible to query the data directly from SQL as if it were relational data. …
What is XML table?
XMLTABLE is a SQL/XML function that is implemented in the FROM clause of a SQL but in combination with a driving table that contains the XML data for translating the XML data to a relational form. Hence, using this Oracle XMLTABLE function one can retrieve several information from the XML data. Syntax.
What is Oracle XQuery?
XQuery Is About Sequences. Querying XML Data in Oracle XML DB Repository using XQuery. Querying Table or View Data using XQuery. Using XQuery with XMLType Data. Using Namespaces with XQuery.
How to query XML column in Oracle?
You can query XML data from XMLType columns in the following ways:
- Select XMLType columns in SQL, PL/SQL, or Java.
- Query XMLType columns directly or using XMLType methods extract() and existsNode() .
- Use Oracle Text operators to query the XML content.
- Use the XQuery language.
What is Oracle XMLType?
Description of XMLType XMLType is a system-defined opaque type for handling XML data. XMLType has predefined member functions on it to extract XML nodes and fragments. You can create columns of XMLType and insert XML documents into it.
What is XML and how it works?
Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. The World Wide Web Consortium’s XML 1.0 Specification of 1998 and several other related specifications—all of them free open standards—define XML.
How does an XML table work in SQL?
XMLTable maps the result of an XQuery evaluation into relational rows and columns. You can query the result returned by the function as a virtual relational table using SQL. The XMLNAMESPACES clause contains a set of XML namespace declarations.
What is the optional column clause in xmltable?
The optional COLUMNS clause defines the columns of the virtual table to be created by XMLTable. If you omit the COLUMNS clause, then XMLTable returns a row with a single XMLType pseudocolumn named COLUMN_VALUE.
Where do I find the XQuery expression in XML table?
The XMLNAMESPACES clause contains a set of XML namespace declarations. These declarations are referenced by the XQuery expression (the evaluated XQuery_string ), which computes the row, and by the XPath expression in the PATH clause of XML_table_column, which computes the columns for the entire XMLTable function.
How to split XML table into different columns?
For example: XMLTable (… COLUMNS xyz XMLTable (… COLUMNS xyz PATH ‘XYZ’) You can use different PATH clauses to split the XQuery result into different virtual-table columns. The optional DEFAULT clause specifies the value to use when the PATH expression results in an empty sequence.