The functions in these examples are designed to decompress LOB-based data that has been algorithmically compressed by the examples in “Example: Creating Functions that Algorithmically Compress LOB-Related Data."
See Teradata Vantage™ - SQL External Routine Programming , B035-1147 for information about how to write the C, C++, or Java code for the external functions these function definitions reference to decompress LOB-related data.
This example creates a UDF named clob_decompress to decompress CLOB columns that were algorithmically compressed using the function clob_compress from Example: Creating Functions that Algorithmically Compress LOB-Related Data.
CREATE FUNCTION clob_decompress (a BLOB AS LOCATOR) RETURNS CLOB AS LOCATOR SPECIFIC clob_decompress LANGUAGE C NO SQL FOR DECOMPRESS PARAMETER STYLE TD_GENERAL RETURNS NULL ON NULL INPUT DETERMINISTIC EXTERNAL NAME 'cs!clobdecompress!clobdecompress.c';
This example creates a UDF named d_clob_decompress to decompress distinct LOB-based UDT columns that were algorithmically compressed using the function d_clob_compress from Example: Creating Functions that Algorithmically Compress LOB-Related Data.
CREATE FUNCTION d_clob_decompress (a BLOB AS LOCATOR) RETURNS DCLOB SPECIFIC d_clob_decompress LANGUAGE C NO SQL FOR DECOMPRESS PARAMETER STYLE TD_GENERAL RETURNS NULL ON NULL INPUT DETERMINISTIC EXTERNAL NAME 'cs!dclobdecompress!dclobdecompress.c';
This example creates a UDF named s_clob_decompress to decompress distinct LOB-based UDT columns that were algorithmically compressed using the function s_clob_compress from Example: Creating Functions that Algorithmically Compress LOB-Related Data.
CREATE FUNCTION s_clob_decompress (a BLOB AS LOCATOR) RETURNS SCLOB SPECIFIC s_clob_decompress LANGUAGE C NO SQL FOR DECOMPRESS PARAMETER STYLE TD_GENERAL RETURNS NULL ON NULL INPUT DETERMINISTIC EXTERNAL NAME 'cs!sclobdecompress!sclobdecompress.c';