Doc: Fix and tweak documentation for ANALYZE reporting

The docs had some typos and grammar mistakes, and its indentation was
inconsistent.

Author: Amit Langote, Justin Pryzby
Discussion: https://postgr.es/m/20200116151930.GM26045@telsasoft.com

doc/src/sgml/monitoring.sgml

@@ -3592,8 +3592,8 @@ SELECT pg_stat_get_backend_pid(s.backendid) AS pid,
      <entry><structfield>ext_stats_computed</structfield></entry>
      <entry><type>bigint</type></entry>
      <entry>
-       Number of computed extended statistics computed.  This counter only advances when
-       the phase is <literal>computing extended statistics</literal>.
+      Number of extended statistics computed. This counter only advances
+      when the phase is <literal>computing extended statistics</literal>.
      </entry>
     </row>
     <row>
@@ -3607,15 +3607,17 @@ SELECT pg_stat_get_backend_pid(s.backendid) AS pid,
      <entry><structfield>child_tables_done</structfield></entry>
      <entry><type>bigint</type></entry>
      <entry>
-       Number of child tables scanned.  This counter only advances when the phase
-       is <literal>acquiring inherited sample rows</literal>.
+      Number of child tables scanned. This counter only advances when the
+      phase is <literal>acquiring inherited sample rows</literal>.
      </entry>
     </row>
     <row>
      <entry><structfield>current_child_table_relid</structfield></entry>
      <entry><type>oid</type></entry>
-     <entry>OID of the child table currently being scanned. This field is only valid when
-       the phase is <literal>computing extended statistics</literal>.
+     <entry>
+      OID of the child table currently being scanned. This field is
+      only valid when the phase is
+      <literal>acquiring inherited sample rows</literal>.
      </entry>
     </row>
    </tbody>
@@ -3643,31 +3645,31 @@ SELECT pg_stat_get_backend_pid(s.backendid) AS pid,
       <entry><literal>acquiring sample rows</literal></entry>
       <entry>
        The command is currently scanning the table given by
-       <structfield>current_relid</structfield> to obtain sample rows.
+       <structfield>relid</structfield> to obtain sample rows.
       </entry>
      </row>
      <row>
       <entry><literal>acquiring inherited sample rows</literal></entry>
       <entry>
-       The command is currently scanning child tables to obtain sample rows. Columns
-       <structfield>child_tables_total</structfield>,
+       The command is currently scanning child tables to obtain sample rows.
+       Columns <structfield>child_tables_total</structfield>,
        <structfield>child_tables_done</structfield>, and
-       <structfield>current_child_table_relid</structfield> contain the progress
-       information for this phase.
+       <structfield>current_child_table_relid</structfield> contain the
+       progress information for this phase.
       </entry>
      </row>
      <row>
       <entry><literal>computing statistics</literal></entry>
       <entry>
-       The command is computing statistics from the samples rows obtained during
-       the table scan.
+       The command is computing statistics from the sample rows obtained
+       during the table scan.
       </entry>
      </row>
      <row>
       <entry><literal>computing extended statistics</literal></entry>
       <entry>
-       The command is computing extended statistics from the samples rows obtained
-       durring the table scan.
+       The command is computing extended statistics from the sample rows
+       obtained during the table scan.
       </entry>
      </row>
      <row>