C UDR using mi_trigger_get_old_row() and mi_trigger_get_new_row()
Jean-Guy Charron's C UDR row_to_json using mi_trigger_get_old_row and mi_trigger_get_new_row received NULL, with mi_trigger_event returning MI_ERROR, when called from an SPL with trigger references. Paul Watson said the functions return NULL outside the trigger action. Jean-Guy sent working and non-working scripts. No solution was given.
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I suspect you are getting a NULL rather that a valid row ptr, I believe it will be NULL cos you are in a SPL An MI_ROW pointer A pointer to the old row. NULL The function was one of the following: not successful. not in the trigger action. not in the FOR EACH row trigger. not in one of the DELETE or UPDATE triggers. On 9/3/2025 3:27 PM, Jean-Guy Charron via IBM TechXchange Community wrote: 01000199114329d4-a23cc2f6-599d-415a-9251-a193c02f6858-000000@email.amazonses.com"> Hi Everyone, I have create a C UDR row_to_json that use mi_trigger_get_old_row() and mi_trigger_get_new_row() to have access to the trigger row... -posted to the "Informix" group
Yes I effectivly received a NULL. But since I call the UDR from an SPL with trigger references I expected to received the old/new row. I just hoped there was a solution. Thanks for your help ------------------------------ Jean-Guy Charron ------------------------------
A real NULl or just crap ? Cheers Paul Paul Watson Oninit LLC +1-913-387-7529 www.oninit.com Oninit® is a registered trademark of Oninit LLC
Yes a NULL And mi_trigger_event() return MI_ERROR (-1) Jean-Guy
Hi Paul, I send the C UDR and a working.sql and a notworking.sql scripts. You will see in the DEBUG* files the tracing. What I need to do, is a generic UDR that take the old/new row and return a lvarchar containing a json of the data excluding TEXT, BYTE, BLOB, CLOB, row, collection, list, ... and limiting lvarchar column to the first 255 characters. After that I can cast it in json and bson to keep a log of change in important tables in a generic log tables. So the working.sql call row_to_json directly from the trigger and pass the value to a SPL procedure with trigger references. The notworking.sql call the row_to_json from the SPL procedure with triggers references. Thanks for your help. Jean-Guy Charron Président Logiciels Sys-Thèmes inc. 514-381-5460 x 202 jeanguy.charron@systhemes.ca systhemes.ca flexio-erp.ca 205-863 St-Pierre, Terrebonne, Qc, J6W 1E6