interact,
     communicating over a <glossterm linkend="glossary-connection">connection</glossterm>.
    </para>
   </glossdef>
  </glossentry>

  <glossentry id="glossary-shared-memory">
   <glossterm>Shared memory</glossterm>
   <glossdef>
    <para>
     <acronym>RAM</acronym> which is used by the processes common to an
     <glossterm linkend="glossary-instance">instance</glossterm>.
     It mirrors parts of <glossterm linkend="glossary-database">database</glossterm>
     files, provides a transient area for
     <glossterm linkend="glossary-wal-record">WAL records</glossterm>,
     and stores additional common information.
     Note that shared memory belongs to the complete instance, not to a single
     database.
    </para>
    <para>
     The largest part of shared memory is known as <firstterm>shared buffers</firstterm>
     and is used to mirror part of data files, organized into pages.
     When a page is modified, it is called a dirty page until it is
     written back to the file system.
    </para>
    <para>
     For more information, see
     <xref linkend="runtime-config-resource-memory"/>.
    </para>
   </glossdef>
  </glossentry>

  <glossentry id="glossary-sql-object">
   <glossterm>SQL object</glossterm>
    <glossdef>
     <para>
      Any object that can be created with a <command>CREATE</command>
      command.  Most objects are specific to one database, and are commonly
      known as <firstterm>local objects</firstterm>.
     </para>
     <para>
      Most local objects reside in a specific
      <glossterm linkend="glossary-schema">schema</glossterm> in their
      containing database, such as
      <glossterm linkend="glossary-relation">relations</glossterm> (all types),
      <glossterm linkend="glossary-function">routines</glossterm> (all types),
      data types, etc.
      The names of such objects of the same type in the same schema
      are enforced to be unique.
     </para>
     <para>
      There also exist local objects that do not reside in schemas; some examples are
      <glossterm linkend="glossary-extension">extensions</glossterm>,
      <glossterm linkend="glossary-cast">data type casts</glossterm>, and
      <glossterm linkend="glossary-foreign-data-wrapper">foreign data wrappers</glossterm>.
      The names of such objects of the same type are enforced to be unique
      within the database.
     </para>
     <para>
      Other object types, such as
      <glossterm linkend="glossary-role">roles</glossterm>,
      <glossterm linkend="glossary-tablespace">tablespaces</glossterm>,
      replication origins, subscriptions for logical replication, and
      databases themselves are not local SQL objects since they exist
      entirely outside of any specific database;
      they are called <firstterm>global objects</firstterm>.
      The names of such objects are enforced to be unique within the whole
      database cluster.
     </para>
    <para>
      For more information, see
      <xref linkend="manage-ag-overview"/>.
    </para>
   </glossdef>
  </glossentry>

  <glossentry id="glossary-sql-standard">
   <glossterm>SQL standard</glossterm>
   <glossdef>
    <para>
     A series of documents that define the <acronym>SQL</acronym> language.
    </para>
   </glossdef>
  </glossentry>

  <glossentry>
   <glossterm>Standby (server)</glossterm>
   <glosssee otherterm="glossary-replica" />
  </glossentry>

  <glossentry id="glossary-startup-process">
   <glossterm>Startup process</glossterm>
   <glossdef>
    <para>
     An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm>
     that replays WAL during crash recovery and in a
     <glossterm linkend="glossary-replication">physical replica</glossterm>.
    </para>
    <para>
     (The name is historical: the startup process was named before
     replication was implemented; the name refers to its task as it
     relates to the server startup following a crash.)
    </para>
   </glossdef>
  </glossentry>

  <glossentry