Running the Sample TPF in tpf_blob.cxx

The sample tpf_blob is included in a precompiled dynamic library called libv4apiex (extension is platform-dependent). Its implementation is in the samples directory in tpf_blob.cxx.

1. Declare the TPF to the server:

   CREATE OR REPLACE PROCEDURE tpf_blob( IN tab TABLE( num INT,
                                                                  s long varchar ),
                                                    IN pattern char(1) )
   RESULT( num INT, s long varchar )
   EXTERNAL NAME 'tpf_blob@libv4apiex';

2. Declare a table to use as input to the TPF:

   CREATE TABLE test_table( val INT, str LONG VARCHAR );

3. Insert rows into the table:

   INSERT INTO test_table VALUES(1, 'aaaaaaaaaabbbbbbbbbb');
   INSERT INTO test_table VALUES(2, 'aaaaaaaaaaabbbbbbbbbbb');
   INSERT INTO test_table VALUES(3, 'aaaaaaaaaaaabbbbbbbbbbbb');
   INSERT INTO test_table VALUES(4, 'aaaaaaaaaaaaabbbbbbbbbbbbb');
   INSERT INTO test_table VALUES(5, 'aaaaaaaaaaaaaabbbbbbbbbbbbbb');
   COMMIT;
   

4. Select rows from the TPF:

   SELECT * FROM tpf_blob( TABLE( SELECT val,str FROM test_table ), 'a' );

   The table test_table has three rows with an even number of as. Row 1 has 10, row 3 has 12, and row 5 has 14.