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refactor: move DBMS_UTILITY to ivorysql_ora per upstream convention
Move DBMS_UTILITY package from plisql to contrib/ivorysql_ora following the IvorySQL built-in package convention. Changes: - Add dbms_utility.c and dbms_utility--1.0.sql to contrib/ivorysql_ora/src/builtin_packages/dbms_utility/ - Use dynamic symbol lookup (dlsym) to call plisql API, avoiding link-time dependency between extensions - Keep minimal API in plisql: plisql_get_current_exception_context() exports exception context for cross-module access - Update Makefile and ivorysql_ora_merge_sqls for new package - Move regression tests to contrib/ivorysql_ora/sql and expected/ - Remove DBMS_UTILITY package definition from plisql--1.0.sql The dynamic lookup approach allows ivorysql_ora.so and plisql.so to be loaded in any order, resolving the symbol at runtime when the function is actually called from within a PL/iSQL exception handler.
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-154
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11 files changed

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-154
lines changed

‎contrib/ivorysql_ora/Makefile‎

Lines changed: 7 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -27,7 +27,8 @@ OBJS = \
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src/builtin_functions/misc_functions.o \
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src/merge/ora_merge.o \
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src/sysview/sysview_functions.o \
30-
src/xml_functions/ora_xml_functions.o
30+
src/xml_functions/ora_xml_functions.o \
31+
src/builtin_packages/dbms_utility/dbms_utility.o
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EXTENSION = ivorysql_ora
3334

@@ -69,10 +70,14 @@ ORA_REGRESS = \
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datatype_and_func_bugs \
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ora_sysview \
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ora_like_operator \
72-
ora_xml_functions
73+
ora_xml_functions \
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dbms_utility
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SHLIB_LINK += -lxml2
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# Include path for plisql.h (needed by dbms_utility)
79+
PG_CPPFLAGS += -I$(top_srcdir)/src/pl/plisql/src
80+
7681
ifdef USE_PGXS
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PG_CONFIG = pg_config
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PGXS := $(shell $(PG_CONFIG) --pgxs)

src/pl/plisql/src/expected/dbms_utility.out renamed to contrib/ivorysql_ora/expected/dbms_utility.out

File renamed without changes.

‎contrib/ivorysql_ora/ivorysql_ora_merge_sqls‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -2,3 +2,4 @@ src/datatype/datatype
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src/builtin_functions/builtin_functions
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src/sysview/sysview
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src/xml_functions/xml_functions
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src/builtin_packages/dbms_utility/dbms_utility

src/pl/plisql/src/sql/dbms_utility.sql renamed to contrib/ivorysql_ora/sql/dbms_utility.sql

File renamed without changes.

‎contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility--1.0.sql‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,26 @@
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/***************************************************************
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*
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* DBMS_UTILITY Package
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*
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* Oracle-compatible utility functions.
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*
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***************************************************************/
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-- C function wrapper for FORMAT_ERROR_BACKTRACE
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CREATE FUNCTION sys.ora_format_error_backtrace() RETURNS TEXT
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AS 'MODULE_PATHNAME', 'ora_format_error_backtrace'
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LANGUAGE C VOLATILE;
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COMMENT ON FUNCTION sys.ora_format_error_backtrace() IS 'Internal function for DBMS_UTILITY.FORMAT_ERROR_BACKTRACE';
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-- DBMS_UTILITY Package Definition
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CREATE OR REPLACE PACKAGE dbms_utility IS
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FUNCTION FORMAT_ERROR_BACKTRACE RETURN TEXT;
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END dbms_utility;
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CREATE OR REPLACE PACKAGE BODY dbms_utility IS
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FUNCTION FORMAT_ERROR_BACKTRACE RETURN TEXT IS
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BEGIN
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RETURN sys.ora_format_error_backtrace();
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END;
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END dbms_utility;

src/pl/plisql/src/pl_dbms_utility.c renamed to contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility.c

Lines changed: 70 additions & 24 deletions
Original file line numberDiff line numberDiff line change
@@ -13,35 +13,77 @@
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* pl_dbms_utility.c
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* dbms_utility.c
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*
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* This file contains the implementation of Oracle's DBMS_UTILITY package
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* functions. These functions are part of the PL/iSQL language runtime
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* because they need access to PL/iSQL internals (exception context, etc.)
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* Implementation of Oracle's DBMS_UTILITY package functions.
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* This module is part of ivorysql_ora extension but calls the PL/iSQL
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* API to access exception context information.
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*
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* Portions Copyright (c) 2025, IvorySQL Global Development Team
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*
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* src/pl/plisql/src/pl_dbms_utility.c
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* contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "fmgr.h"
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#include "funcapi.h"
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#include "catalog/pg_collation.h"
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#include "catalog/pg_proc.h"
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#include "catalog/pg_namespace.h"
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#include "utils/builtins.h"
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#include "utils/elog.h"
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#include "utils/formatting.h"
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#include "utils/lsyscache.h"
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#include "utils/syscache.h"
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#include "mb/pg_wchar.h"
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#include "plisql.h"
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#ifndef WIN32
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#include <dlfcn.h>
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#endif
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PG_FUNCTION_INFO_V1(ora_format_error_backtrace);
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/*
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* Function pointer type for plisql_get_current_exception_context.
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* We use dynamic lookup to avoid link-time dependency on plisql.so.
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*/
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typedef const char *(*plisql_get_context_fn)(void);
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/*
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* Cached function pointer for plisql_get_current_exception_context.
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* Looked up once on first use.
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*/
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static plisql_get_context_fn get_exception_context_fn = NULL;
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static bool lookup_attempted = false;
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/*
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* Look up the plisql_get_current_exception_context function dynamically.
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* Returns the function pointer, or NULL if not found.
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*/
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static plisql_get_context_fn
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lookup_plisql_get_exception_context(void)
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{
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void *fn;
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if (lookup_attempted)
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return get_exception_context_fn;
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lookup_attempted = true;
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#ifndef WIN32
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/*
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* Use RTLD_DEFAULT to search all loaded shared objects.
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* plisql.so should already be loaded when this function is called
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* from within a PL/iSQL exception handler.
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*/
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fn = dlsym(RTLD_DEFAULT, "plisql_get_current_exception_context");
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if (fn != NULL)
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get_exception_context_fn = (plisql_get_context_fn) fn;
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#else
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/*
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* On Windows, we'd need to use GetProcAddress with the module handle.
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* For now, just return NULL - this feature requires plisql.
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*/
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fn = NULL;
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#endif
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return get_exception_context_fn;
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}
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/*
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* Transform a single line from PostgreSQL error context format to Oracle format.
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*
@@ -152,8 +194,7 @@ transform_and_append_line(StringInfo result, const char *line)
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pfree(func_name);
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pfree(func_upper);
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pfree(schema_upper);
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if (schema_name)
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pfree(schema_name);
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pfree(schema_name);
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return true;
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}
@@ -164,9 +205,8 @@ transform_and_append_line(StringInfo result, const char *line)
164205
* Returns formatted error backtrace string in Oracle format.
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* Returns NULL if not in exception handler context.
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*
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* This Oracle-compatible function automatically retrieves the exception
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* context from PL/iSQL's session storage, which is set when entering
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* an exception handler.
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* This Oracle-compatible function retrieves the exception context from
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* PL/iSQL via dynamic lookup of plisql_get_current_exception_context().
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*/
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Datum
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ora_format_error_backtrace(PG_FUNCTION_ARGS)
@@ -176,9 +216,18 @@ ora_format_error_backtrace(PG_FUNCTION_ARGS)
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char *line;
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char *saveptr;
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StringInfoData result;
219+
plisql_get_context_fn get_context;
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/* Look up the PL/iSQL function dynamically */
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get_context = lookup_plisql_get_exception_context();
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if (get_context == NULL)
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{
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/* plisql not loaded or function not found */
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PG_RETURN_NULL();
227+
}
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180-
/* Get the current exception context from PL/iSQL session storage */
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pg_context = plisql_get_current_exception_context();
229+
/* Get the current exception context from PL/iSQL */
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pg_context = get_context();
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/* If no context available (not in exception handler), return NULL */
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if (pg_context == NULL || pg_context[0] == '\0')
@@ -202,8 +251,5 @@ ora_format_error_backtrace(PG_FUNCTION_ARGS)
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pfree(context_copy);
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/* Oracle always ends with a newline - don't remove it */
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/* The transform_and_append_line function already adds newlines */
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PG_RETURN_TEXT_P(cstring_to_text(result.data));
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}

‎design/dbms_utility/PROPOSAL.md‎

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# DBMS_UTILITY Implementation Proposal
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## Summary
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This proposal describes an implementation approach for `DBMS_UTILITY.FORMAT_ERROR_BACKTRACE` that follows IvorySQL's built-in package convention while addressing the cross-module dependency challenge.
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## Background
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Oracle's `DBMS_UTILITY.FORMAT_ERROR_BACKTRACE` returns the call stack at the point where an exception was raised. This requires access to exception context information that is internal to PL/iSQL's execution state.
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## The Challenge
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IvorySQL has two independent modules:
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```
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src/pl/plisql/src/ → plisql.so (PL/iSQL language runtime)
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contrib/ivorysql_ora/ → ivorysql_ora.so (Oracle compatibility extension)
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```
19+
20+
The built-in package convention places packages in `contrib/ivorysql_ora/src/builtin_packages/`. However, `FORMAT_ERROR_BACKTRACE` needs access to PL/iSQL's exception context (`edata->context`), which is only available inside PL/iSQL's `exec_stmt_block()` during exception handling.
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## Proposed Solution
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Split the implementation between modules with a minimal API boundary:
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### 1. Minimal API in `plisql` (5-10 lines)
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Add a single accessor function to expose the exception context:
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```c
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// src/pl/plisql/src/pl_exec.c
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static PLiSQL_execstate *exception_handling_estate = NULL;
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const char *
36+
plisql_get_current_exception_context(void)
37+
{
38+
if (exception_handling_estate != NULL &&
39+
exception_handling_estate->cur_error != NULL)
40+
return exception_handling_estate->cur_error->context;
41+
return NULL;
42+
}
43+
```
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Track `exception_handling_estate` when entering/exiting exception handlers:
46+
47+
```c
48+
// In exec_stmt_block(), when entering exception handler:
49+
exception_handling_estate = estate;
50+
rc = exec_stmts(estate, exception->action);
51+
exception_handling_estate = save_exception_handling_estate;
52+
```
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Export in header:
55+
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```c
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// src/pl/plisql/src/plisql.h
58+
extern PGDLLEXPORT const char *plisql_get_current_exception_context(void);
59+
```
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### 2. DBMS_UTILITY Package in `ivorysql_ora`
62+
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```
64+
contrib/ivorysql_ora/
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├── src/builtin_packages/
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│ └── dbms_utility/
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│ ├── dbms_utility.c ← C code (format transformation)
68+
│ └── dbms_utility--1.0.sql ← Package definition
69+
├── sql/dbms_utility.sql ← Regression tests
70+
├── expected/dbms_utility.out
71+
├── Makefile ← Add dbms_utility.o
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└── ivorysql_ora_merge_sqls ← Add entry
73+
```
74+
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The C code calls the plisql API and transforms the output:
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```c
78+
// contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility.c
79+
80+
#include "plisql.h" // For plisql_get_current_exception_context()
81+
82+
Datum
83+
ora_format_error_backtrace(PG_FUNCTION_ARGS)
84+
{
85+
const char *pg_context = plisql_get_current_exception_context();
86+
if (pg_context == NULL)
87+
PG_RETURN_NULL();
88+
89+
// Transform PostgreSQL format to Oracle format:
90+
// "PL/iSQL function foo() line 3 at RAISE"
91+
// → "ORA-06512: at \"PUBLIC.FOO\", line 3"
92+
...
93+
}
94+
```
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96+
## File Changes Summary
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### `plisql` Changes (Minimal)
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100+
| File | Change |
101+
|------|--------|
102+
| `src/pl/plisql/src/pl_exec.c` | Add `exception_handling_estate` tracking + API function (~20 lines) |
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| `src/pl/plisql/src/plisql.h` | Add API declaration (1 line) |
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### `ivorysql_ora` Changes (Main Implementation)
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107+
| File | Change |
108+
|------|--------|
109+
| `contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility.c` | New - C implementation |
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| `contrib/ivorysql_ora/src/builtin_packages/dbms_utility/dbms_utility--1.0.sql` | New - Package definition |
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| `contrib/ivorysql_ora/sql/dbms_utility.sql` | New - Regression tests |
112+
| `contrib/ivorysql_ora/expected/dbms_utility.out` | New - Expected output |
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| `contrib/ivorysql_ora/Makefile` | Add `dbms_utility.o` |
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| `contrib/ivorysql_ora/ivorysql_ora_merge_sqls` | Add entry |
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## Why This Approach?
117+
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1. **Follows convention**: DBMS_UTILITY lives in `contrib/ivorysql_ora/src/builtin_packages/`
119+
2. **Minimal plisql changes**: Only a small API (~20 lines), no package code
120+
3. **Clean API boundary**: `plisql_get_current_exception_context()` is a stable interface
121+
4. **Uses existing data**: Leverages `estate->cur_error` which PL/iSQL already maintains
122+
5. **No new struct fields**: Uses existing `ErrorData.context` field
123+
124+
## Alternative Considered
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126+
Implement everything in `plisql`:
127+
- Simpler (no cross-module coordination)
128+
- But doesn't follow built-in package convention
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- Future DBMS packages would be inconsistent
130+
131+
## Questions for IvorySQL Team
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1. Is adding a minimal API to `plisql` acceptable for packages that need PL/iSQL internals?
134+
2. Should this API pattern be documented as the standard approach for such packages?
135+
3. Are there any concerns about the `PGDLLEXPORT` approach for cross-module calls?
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## References
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- [Oracle DBMS_UTILITY.FORMAT_ERROR_BACKTRACE](https://docs.oracle.com/en/database/oracle/oracle-database/23/arpls/DBMS_UTILITY.html#GUID-D72B928F-C353-461D-B098-83865F295C55)
140+
- Existing IvorySQL built-in packages: `contrib/ivorysql_ora/src/builtin_functions/`
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---
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**Author:** [Your Name]
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**Date:** 2025-12-02
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**Status:** Proposal

‎src/pl/plisql/src/Makefile‎

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@@ -41,7 +41,6 @@ OBJS = \
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$(WIN32RES) \
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pl_autonomous.o \
4343
pl_comp.o \
44-
pl_dbms_utility.o \
4544
pl_exec.o \
4645
pl_funcs.o \
4746
pl_gram.o \

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