Oracle Corporation
Map of operations for ingesting external data

Abstract:

Techniques are described for generating a map of operations to ingest external data. In an embodiment, DBMS receives a query schema that specifies an external data source and client-defined columns to arrange queried data from data fields of the external data source. DBMS generates an ingest schema for the queried data of the external data source such that the ingest schema specifies ingest data fields from the data fields of the external data source to be mapped to the one or more client-defined columns. Additionally, the DBMS identifies surplus data in the external data source, which has not been specified by the ingest schema and is different from the queried data defined by the client-requested query schema. The process not only ingests the ingest data fields from the external data source but also the surplus data from the external data source. In response to receiving a query according to a different query schema, DBMS generates a result set that based on the surplus data of the external data source. The result generation is based on the DBMS generating a map of operations, which when performed, generates a result set for the received query regardless whether the query is based on the different query schema.