AB_SQL - Streaming AB_SQL supports streaming for LOBs in data sources. ITOC
System Classes and System Interfaces for Reader and Writer Streams The system classes for the various types of data streams are:
CL_ABAP_DB_C_READER for character-like reader streams. The streaming data source is a CLOB.
CL_ABAP_DB_X_READER for binary reader streams. The streaming data source a BLOB.
CL_ABAP_DB_C_WRITER for character-like writer streams. The streaming data sink is a CLOB.
CL_ABAP_DB_X_WRITER for binary writer streams. The streaming data sink a BLOB. The special interfaces
IF_ABAP_DB_READER
IF_ABAP_DB_WRITER are used to access the reader and writer streams independently of the stream type. For further resource-independent classes and interfaces, as well as for the hierarchy of the object types, see the figure and explanation under Streaming.
Important Methods The methods for streaming in AB_SQL are the same as for general streaming.
Data Sources and Data Sinks Any LOBs declared in DDIC database tables can be considered as data sources or data sinks. The instances of the classes above are data streams bound to LOBs. These are LOB handles and implement the corresponding interfaces. Their use in AB_SQL involves reference variables that point to the relevant LOB handles.
Creating Data Streams for LOBs
Reader Streams A reader stream that is bound to an LOB, that is, an instance of the class CL_ABAP_DB_C_READER or CL_ABAP_DB_X_READER, can only be created by assigning a LOB from the result set to a reference variable for a reader stream in the INTO clause of the statement SELECT. See SELECT - LOB Handles.
