Clarify when aborted rows are tracked for tuple related counters.

It is not obvious from the statistics collector documentation that
tuple-related counters are incremented even when a transaction aborts,
except for the n_mod_since_analyze counter, which only counts committed
rows. Update the documentation to clarify this behavior.

Author: samimseih

doc/src/sgml/monitoring.sgml

@@ -283,6 +283,10 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
    stated above; instead they update continuously throughout the transaction.
   </para>
 
+  <para>
+   An aborted transaction will also increment tuple-related counters, unless otherwise noted.
+  </para>
+
   <para>
    Some of the information in the dynamic statistics views shown in <xref
    linkend="monitoring-stats-dynamic-views-table"/> is security restricted.
@@ -3963,7 +3967,8 @@ description | Waiting for a newly initialized WAL file to reach durable storage
        <structfield>n_live_tup</structfield> <type>bigint</type>
       </para>
       <para>
-       Estimated number of live rows
+       Estimated number of live rows (updated by committed transactions, or by
+       <command>VACUUM</command> and <command>VACUUM FULL</command>)
       </para></entry>
      </row>
 
@@ -3972,7 +3977,8 @@ description | Waiting for a newly initialized WAL file to reach durable storage
        <structfield>n_dead_tup</structfield> <type>bigint</type>
       </para>
       <para>
-       Estimated number of dead rows
+       Estimated number of dead rows (updated either by committed or aborted
+       transactions, or by <command>VACUUM</command> and <command>VACUUM FULL</command>)
       </para></entry>
      </row>
 
@@ -3981,7 +3987,8 @@ description | Waiting for a newly initialized WAL file to reach durable storage
        <structfield>n_mod_since_analyze</structfield> <type>bigint</type>
       </para>
       <para>
-       Estimated number of rows modified since this table was last analyzed
+       Estimated number of rows modified (by committed transactions) since this table
+       was last analyzed
       </para></entry>
      </row>