XML and Data Models

Sean McGrath writes...

Quote from Date defends relational model: "XML is not a real data model." Discuss :-)

The way I see it "XML" is a data format. So then what is a data model?

• "hierarchy" is a data model
• "binary tree" is a data model
• "[un]directed graph" is a data model
• "star schema" is a data model
• "table" is a data model
• "ordered sequence" is a data model

Each of these can be represented in XML files, in a "native" XML database, in a relational database, and in many other formats. How suitable each format is depends on the data and how you intend to use it.