Add progress reporting of skipped tuples during COPY FROM.

9e2d870119 enabled the COPY command to skip malformed data, however
there was no visibility into how many tuples were actually skipped
during the COPY FROM.

This commit adds a new "tuples_skipped" column to
pg_stat_progress_copy view to report the number of tuples that were
skipped because they contain malformed data.

Bump catalog version.

Author: Atsushi Torikoshi
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/d12fd8c99adcae2744212cb23feff6ed%40oss.nttdata.com

doc/src/sgml/monitoring.sgml

@@ -5780,6 +5780,18 @@ FROM pg_stat_get_backend_idset() AS backendid;
        <command>WHERE</command> clause of the <command>COPY</command> command.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>tuples_skipped</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of tuples skipped because they contain malformed data.
+       This counter only advances when a value other than
+       <literal>stop</literal> is specified to the <literal>ON_ERROR</literal>
+       option.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>

src/backend/catalog/system_views.sql

@@ -1318,7 +1318,8 @@ CREATE VIEW pg_stat_progress_copy AS
         S.param1 AS bytes_processed,
         S.param2 AS bytes_total,
         S.param3 AS tuples_processed,
-        S.param4 AS tuples_excluded
+        S.param4 AS tuples_excluded,
+        S.param7 AS tuples_skipped
     FROM pg_stat_get_progress_info('COPY') AS S
         LEFT JOIN pg_database D ON S.datid = D.oid;
 

src/backend/commands/copyfrom.c

@@ -650,6 +650,7 @@ CopyFrom(CopyFromState cstate)
 	CopyMultiInsertInfo multiInsertInfo = {0};	/* pacify compiler */
 	int64		processed = 0;
 	int64		excluded = 0;
+	int64		skipped = 0;
 	bool		has_before_insert_row_trig;
 	bool		has_instead_insert_row_trig;
 	bool		leafpart_use_multi_insert = false;
@@ -1012,6 +1013,10 @@ CopyFrom(CopyFromState cstate)
 				 */
 				cstate->escontext->error_occurred = false;
 
+			/* Report that this tuple was skipped by the ON_ERROR clause */
+			pgstat_progress_update_param(PROGRESS_COPY_TUPLES_SKIPPED,
+										 ++skipped);
+
 			continue;
 		}
 

src/include/catalog/catversion.h

@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202401241
+#define CATALOG_VERSION_NO	202401251
 
 #endif

src/include/commands/progress.h

@@ -142,6 +142,7 @@
 #define PROGRESS_COPY_TUPLES_EXCLUDED 3
 #define PROGRESS_COPY_COMMAND 4
 #define PROGRESS_COPY_TYPE 5
+#define PROGRESS_COPY_TUPLES_SKIPPED 6
 
 /* Commands of COPY (as advertised via PROGRESS_COPY_COMMAND) */
 #define PROGRESS_COPY_COMMAND_FROM 1

src/test/regress/expected/rules.out

@@ -1988,7 +1988,8 @@ pg_stat_progress_copy| SELECT s.pid,
     s.param1 AS bytes_processed,
     s.param2 AS bytes_total,
     s.param3 AS tuples_processed,
-    s.param4 AS tuples_excluded
+    s.param4 AS tuples_excluded,
+    s.param7 AS tuples_skipped
    FROM (pg_stat_get_progress_info('COPY'::text) s(pid, datid, relid, param1, param2, param3, param4, param5, param6, param7, param8, param9, param10, param11, param12, param13, param14, param15, param16, param17, param18, param19, param20)
      LEFT JOIN pg_database d ON ((s.datid = d.oid)));
 pg_stat_progress_create_index| SELECT s.pid,