Get Example source ABAP code based on a different SAP table
Deriving LOB Handle Structures This example demonstrates how LOB handle structures are derived using the statement TYPES.
ABAP_SOURCE_CODE DEMO CL_DEMO_TYPES_LOB_HANDLE
ABAP_DESCRIPTION The package-visible area of the class demo_lob_handles contains different derivations of LOB handle structures from the database table DEMO_LOB_TABLE. The methods of this class are used to output of the static type of the derived LOB handle components. The DEMO_LOB_TABLE database table contains a key field of type INT4, as well as three columns CLOB1, CLOB2 , CLOB3 of type STRING and three columns BLOB1, BLOB2, BLOB3 of type RAWSTRING. The derivations listed here work as follows:
In the structured type lob_handle_structure_1, clob1 and blob1 become LOB handle components by column specifications directly after READER. The component clob1 contains the static type CL_ABAP_DB_C_READER and blob1 contains the static type CL_ABAP_DB_X_READER. All other components are represented in accordance with the regular rules for their built-in types.
In the structured type lob_handle_structure_2, all LOB components are converted into LOB handle components by specifying FOR ALL COLUMNS. The static type of the components of type STRING is IF_ABAP_DB_CLOB_HANDLE and the static type for the components of type RAWSTRING is IF_ABAP_DB_BLOB_HANDLE .
In the structured type lob_handle_structure_3, all LOB components are converted into LOB handle components. The static type of the components of type STRING is converted into CL_ABAP_DB_C_WRITER by specifying WRITER FOR ALL CLOB COLUMNS and the static type for the components of type RAWSTRING is converted into CL_ABAP_DB_X_LOCATOR by specifying LOCATOR FOR ALL BLOB COLUMNS.
In the structured type lob_handle_structure_4, all LOB components are converted into LOB handle components. The static type of the components clob1 and clob2 is converted into CL_ABAP_DB_C_READER by specifying READER directly. All components of the type RAWSTRING are converted into reference types for IF_ABAP_DB_BLOB_HANDLE by specifying LOB HANDLE FOR ALL BLOB COLUMNS. The remaining components of the type STRING are converted into reference types for CL_ABAP_DB_C_LOCATOR by specifying LOCATOR FOR ALL OTHER CLOB COLUMNS.
In the structured type lob_handle_structure_5, all LOB components are listed directly, and thus converted into the corresponding LOB handle components with the static types CL_ABAP_DB_C_LOCATOR for clob1, clob2, and clob3 and CL_ABAP_DB_X_READER for blob1, blob2, and blob3. The specification LOB HANDLE FOR ALL OTHER COLUMNS has no direct effect, but only affects any enhancements to the database table with further LOBs, which then preserve their type-compliant interface reference type.
In the structured type lob_handle_structure_6, all LOB components are converted into handle LOB components, whereby here the maximum number of column specifications is demonstrated. FOR ALL CLOB COLUMNS can only be specified since no components of type STRING were covered by previous statements.
