12.25. OData Translator 12.25.1. OData Translator The OData translator exposes the OData V2 and V3 data sources. This translator implements a simple connection for web services in the same way as the Web Services translator. The OData translator is implemented by the org.teiid.translator.odata.ODataExecutionFactory class and known by the translator type name odata . Note Open Data Protocol (OData) is a Web protocol for querying and updating data that provides a way to unlock your data and free it from silos that exist in applications today. OData does this by applying and building upon Web technologies such as HTTP, Atom Publishing Protocol (AtomPub) and JSON to provide access to information from a variety of applications, services, and stores. OData is being used to expose and access information from a variety of sources including, but not limited to, relational databases, file systems, content management systems and traditional Web sites. Using this specification from OASIS group, and with the help from framework OData4J , JBoss Data Virtualization maps OData entities into relational schema. JBoss Data Virtualization supports reading of CSDL (Conceptual Schema Definition Language) from the OData endpoint provided and converts the OData schema into relational schema. The below table shows the mapping selections in OData Translator from CSDL document. OData Mapped to Relational Entity EntitySet Table FunctionImport Procedure AssociationSet Foreign Keys on the Table* ComplexType ignored** * A Many to Many association will result in a link table that can not be selected from, but can be used for join purposes. ** When used in Functions, an implicit table is exposed. When used to define a embedded table, all the columns will be in-lined. All CRUD operations will be appropriately mapped to the resulting entity based on the SQL submitted to the OData translator. Note The resource adapter for this translator is provided by configuring the webservice data source in the JBoss EAP instance. See the Red Hat JBoss Data Virtualization Administration and Configuration Guide for more configuration information. Using this specification from OASIS group, with the help from the Olingo framework, Teiid maps OData V4 CSDL (Conceptual Schema Definition Language) document from the OData endpoint provided and converts the OData metadata into Teiid's relational schema. The below table shows the mapping selections in OData V4 Translator from CSDL document 12.25.2. OData Translator: Execution Properties Table 12.21. Execution Properties Name Description Default DatabaseTimeZone The time zone of the database. Used when fetching date, time, or timestamp values The system default time zone 12.25.3. OData Translator: Importer Properties Table 12.22. Importer Properties Name Description Default schemaNamespace Namespace of the schema to import null entityContainer Entity Container Name to import default container Example importer settings to only import tables and views from NetflixCatalog: 12.25.4. OData Translator: Usage Usage of an OData source is similar to a JDBC translator. The metadata import is supported through the translator, once the metadata is imported from source system and exposed in relational terms, then this source can be queried as if the EntitySets and Function Imports were local to the JBoss Data Virtualization system. Table 12.23. Execution Properties Property Description Default DatabaseTimeZone The time zone of the database. Used when fetchings date, time, or timestamp values The system default time zone SupportsOdataCount Supports USDcount True SupportsOdataFilter Supports USDfilter True SupportsOdataOrderBy Supports USDorderby true SupportsOdataSkip Supports USDskip True SupportsOdataTop Supports USDtop True Table 12.24. Importer Properties Property Description Default schemaNamespace Namespace of the schema to import Null entityContainer Entity Container Name to import Default container Here are some importer settings to import tables and views only from NetflixCatalog: Note Sometimes it's possible that the odata server you are querying does not fully implement all OData specification features. If your OData implementation does not support a certain feature, then turn off the corresponding capability using "execution Properties", so that Teiid will not pushdown invalid queries to the translator. For example, to turn off USDfilter you add following to your vdb.xml then use "odata-override" as the translator name on your source model: Note Native or direct query execution is not supported through OData translator. However, user can use Web Services Translator's invokehttp method directly to issue a Rest based call and parse results using SQLXML. Note Teiid can not only consume OData based data sources, but it can expose any data source as an Odata based webservice. For more information see OData Support.

Commands:
<property name="importer.schemaNamespace" value="System.Data.Objects"/> <property name="importer.schemaPattern" value="NetflixCatalog"/>
<property name="importer.schemaNamespace" value="System.Data.Objects"/> <property name="importer.schemaPattern" value="NetflixCatalog"/>
<translator name="odata-override" type="odata"> <property name="SupportsOdataFilter" value="false"/> </translator>