Specifies the data model configuration to use when parsing XML/JSON documents and generating the database metadata. The value supplied here controls how the driver models nested object arrays into tables.

Possible Values

Document, FlattenedDocuments, Relational

データ型

string

デフォルト値

"Document"

解説

The 本製品 splits JSON documents into rows based on the objects nested in arrays. The following subsections describe how that works in each of the three supported configurations. For examples of how to query data in each of the different configurations, see 階層データの解析.

Document

Returns a single table representing a row for each top-level object. Nested object arrays that may exist are not flattened, and are returned as aggregates.

If you explicitly specify an XPath value, the 本製品 uses that XPath. If you do not, the 本製品 identifies the top-most object array found, and uses that as the XPath.

FlattenedDocuments

Returns a single table representing a JOIN of the available documents in the file. Nested XPath values act in the same manner as a SQL JOIN, and nested sibling XPath values (child paths at the same height), are treated as a SQL CROSS JOIN.

If you explicitly identify the XPath values to use, the 本製品 uses those. If you do not, the 本製品 parses the file and identifies the available documents, including nested documents, and uses those as the XPath values.

Relational

Returns multiple tables, one for each XPath value specified. Nested documents (object arrays) are returned as relational tables that contain a primary key and a foreign key that links to the parent table. If you explicitly identify the XPath values to use, the 本製品 uses those. If you do not, the 本製品 parses the file and identifies the available documents, including nested documents, and uses those as the XPath values.

See Also

• XPath: Explicitly sets the paths to the XML documents you want to include.
• FlattenArrays and FlattenObjects: Customizes the columns that will be identified for each of these data models. For examples, see 自動スキーマ検出.
• 階層データの解析: Compares the schemas resulting from different DataModel settings, with example queries.
• For details about the data modeling and flattening techniques available in this 本製品, see REST データのモデリング.