Errors while using plsql clob document in notification email

Question

bq. hello
I am having a problem sending a plsql clob document in a notification email.Basically the procedure retrives some rows of data from the database and formats it as HTML before converting to clob. The email is generated fine when only a couple of rows are generated. however when the rows increase the workflow errors. we are using oracle ERP
---------------------------------Error Message-----
An Error occurred in the following Event Subscription: Event Subscription
Event Error Name: WFE_DISPATCH_GEN_ERR
Event Error Message: 3835: Error '-20002 - ORA-20002: 2018: Unable to generate the notification XML. Caused by: 2020: Error when getting notification content. Caused by: ORA-06502: PL/SQL: numeric or value error: character string buffer too small
Wf_Notification.NTF_Table(8, H)
BATCH_INFO.Batch Information(209112, text/html)
Wf_Notification.GetAttrClob(263883, BATCH_INFO, text/html)
Wf_Notification.oldGetAttrClob(263883, BATCH_INFO, text/html)
WF_NOTIFICATION.GetFullBody(nid => 263883, disptype => text/html)
WF_MAIL.GetLOBMessage3(nid => 263883, ' encountered during execution of Generate function 'WF_XML.Generate' for event 'oracle.apps.wf.notification.send'.
Event Error Stack:
WF_MAIL.GetLOBMessage3(263883, WFMAIL, 2020: Error when getting notification content. Caused by: ORA-06502: PL/SQL: numeric or value error: character string buffer too small
Wf_Notification.NTF_Table(8, H)
BATCH_INFO.Batch Information(209112, text/html)
Wf_Notification.GetAttrClob(263883, BATCH_INFO, text/html)
Wf_Notification.oldGetAttrClob(263883, BATCH_INFO, text/html)
WF_NOTIFICATION.GetFullBody(nid => 263883, disptype => text/html)
WF_MAIL.GetLOBMessage3(nid => 263883, r_ntf_pref => MAILHTML), Step -> Getting text/html body)
WF_XML.GenerateDoc(oracle.apps.wf.notification.send, 263883)
WF_XML.Generate(oracle.apps.wf.notification.send, 263883)
WF_XML.Generate(oracle.apps.wf.notification.send, 263883)
Wf_Event.setMessage(oracle.apps.wf.notification.send, 263883, WF_XML.Generate)
Wf_Event.dispatch_internal()
The Procedure is
bq. /********************************************************************************* \\ Procedure: BATCH_INFO \\ Purpose: Program displays batch level information. \\ *********************************************************************************/ \\ PROCEDURE batch_info ( \\ document_id IN VARCHAR2, \\ display_type IN VARCHAR2, \\ document IN OUT NOCOPY CLOB, \\ document_type IN OUT NOCOPY VARCHAR2 \\ ) \\ IS \\ table_width VARCHAR2 (8) := '100%'; \\ i PLS_INTEGER; \\ j PLS_INTEGER; \\ l_cells wf_notification.tdtype; \\ l_result VARCHAR2 (32767); \\ l_je_batch_name VARCHAR2 (100); \\ l_period_name VARCHAR2 (15); \\ l_control_total NUMBER; \\ l_running_total_dr NUMBER; \\ l_running_total_cr NUMBER; \\ l_document long; \\ cdoc clob; \\ amount NUMBER; \\ charbuff VARCHAR2(32767); \\ charbuff_size NUMBER; \\ CURSOR c_get_je (batch_id IN NUMBER) \\ IS \\ SELECT (SELECT description \\ FROM gl_lookups \\ WHERE lookup_type = 'BATCH_STATUS' \\ AND lookup_code = batch_status) batch_status, \\ je_source, \\ (SELECT user_je_category_name \\ FROM gl_je_categories \\ WHERE je_category_name = je_category) je_category, \\ period_name, batch_name, header_name, \\ header_running_total_dr_num debit, \\ header_running_total_cr_num credit \\ FROM apps.gl_je_batches_headers_v \\ WHERE je_batch_id = batch_id; \\ BEGIN \\ IF display_type = wf_notification.doc_text \\ THEN \\ document := NULL; \\ ELSE \\ /* ===========Second table Start=============*/ \\ j := 0; \\ i := 0; \\ j := 1; \\ /* Header*/ \\ l_cells (j) := 'S:' || 'Batch Status'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Journal Source'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Journal Category'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Period'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Batch Name'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Journal Name'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Journal Debit'; \\ j := j + 1; \\ l_cells (j) := 'S:' || 'Journal Credit'; \\ j := j + 1; \\ i := 0; \\ /* Body*/ \\ SELECT NAME, default_period_name, control_total, \\ running_total_dr, running_total_cr \\ INTO l_je_batch_name, l_period_name, l_control_total, \\ l_running_total_dr, l_running_total_cr \\ FROM gl.gl_je_batches \\ WHERE je_batch_id = TO_NUMBER (document_id); \\ FOR histr IN c_get_je (TO_NUMBER (document_id)) \\ LOOP \\ l_cells (j) := 'S:' || histr.batch_status; \\ j := j + 1; \\ l_cells (j) := 'S:' || histr.je_source; \\ j := j + 1; \\ l_cells (j) := 'S:' || histr.je_category; \\ j := j + 1; \\ l_cells (j) := 'S:' || histr.period_name; \\ j := j + 1; \\ l_cells (j) := 'S:' || histr.batch_name; \\ j := j + 1; \\ l_cells (j) := 'S:' || histr.header_name; \\ j := j + 1; \\ l_cells (j) := \\ 'S:' \\ || NVL (TO_CHAR (histr.debit, \\ 'L999G999G999G999G999G999G999D99'), \\ '&' || 'nbsp;' \\ ); \\ j := j + 1; \\ l_cells (j) := \\ 'S:' \\ || NVL (TO_CHAR (histr.credit, \\ 'L999G999G999G999G999G999G999D99' \\ ), \\ '&' || 'nbsp;' \\ ); \\ j := j + 1; \\ i := i + 1; \\ END LOOP; \\ table_width := '100%'; \\ wf_notification.ntf_table (l_cells, 8, 'HL', l_result); \\ /* Write data to clob */ \\ -- create temp clob \\ dbms_lob.createTemporary(cdoc,false,dbms_lob.call); \\ charbuff_size:=length(l_result); \\ write html data to temp clob \\ dbms_lob.writeappend(cdoc,charbuff_size,l_result); \\ write temp clob to document \\ amount:=dbms_lob.getlength(cdoc); \\ dbms_lob.copy(document,cdoc,amount,1,1); \\ END IF; \\ document_type := 'text/html'; \\ EXCEPTION \\ WHEN OTHERS \\ THEN \\ wf_core.CONTEXT ('BATCH_INFO', 'Batch Information', document_id,display_type); \\ RAISE; \\ END batch_info;
Can somebody please guide me
thank you

Answer 1

The stack trace below the "ORA-06502: PL/SQL: numeric or value error: character string buffer too small" error suggests that this is being generated by the Wf_Notification.NTF_Table call. Given the way you have described the problem, I would assume that the HTML generated by that call for the data in l_cells is exceeding the length of your l_result variable (32767).
Have you checked the length of the data generated by this call for a single record and then divided 32767 by that number to work out the maximum number of rows you can support with this call?
If it is simply that you have too much data for WF_Notification.NTF_Table to produce the table within the 32767 limit, you try generating the HTML in smaller chunks and adding them to the CLOB bit by bit. For example, if 10 records work, then generate the HTML for 10 records, chop off the </table> from the result and add it to the clob. Then do the next 10 records (without the header this time) and chop off the <table> and </table> tags and add that to the clob. When you are done, add the closing </table> tag to the clob and return it.
I haven't done this with returning a clob, but I have done this with shorter strings to generate a HTML table with the standard look and feel but with headers in different places than could be done by default.
theFurryOne