Remove uses of "slave" in replication contexts

This affects mostly code comments, some documentation, and tests.
Official APIs already used "standby".

Author: petere

contrib/dblink/expected/dblink.out

@@ -270,7 +270,7 @@ SELECT *
 FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
 WHERE t.a > 7;
 ERROR:  connection not available
--- put more data into our slave table, first using arbitrary connection syntax
+-- put more data into our table, first using arbitrary connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec(connection_parameters(),'INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
  substr 
@@ -285,7 +285,7 @@ SELECT dblink_connect(connection_parameters());
  OK
 (1 row)
 
--- put more data into our slave table, using persistent connection syntax
+-- put more data into our table, using persistent connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec('INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
  substr 
@@ -610,7 +610,7 @@ SELECT dblink_connect('myconn',connection_parameters());
  OK
 (1 row)
 
--- put more data into our slave table, using named persistent connection syntax
+-- put more data into our table, using named persistent connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
  substr 

contrib/dblink/sql/dblink.sql

@@ -160,14 +160,14 @@ SELECT *
 FROM dblink('SELECT * FROM foo') AS t(a int, b text, c text[])
 WHERE t.a > 7;
 
--- put more data into our slave table, first using arbitrary connection syntax
+-- put more data into our table, first using arbitrary connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec(connection_parameters(),'INSERT INTO foo VALUES(10,''k'',''{"a10","b10","c10"}'')'),1,6);
 
 -- create a persistent connection
 SELECT dblink_connect(connection_parameters());
 
--- put more data into our slave table, using persistent connection syntax
+-- put more data into our table, using persistent connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec('INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
 
@@ -316,7 +316,7 @@ WHERE t.a > 7;
 -- create a named persistent connection
 SELECT dblink_connect('myconn',connection_parameters());
 
--- put more data into our slave table, using named persistent connection syntax
+-- put more data into our table, using named persistent connection syntax
 -- but truncate the actual return value so we can use diff to check for success
 SELECT substr(dblink_exec('myconn','INSERT INTO foo VALUES(11,''l'',''{"a11","b11","c11"}'')'),1,6);
 

doc/src/sgml/high-availability.sgml

@@ -40,7 +40,7 @@
   server to modify the data.  Servers that can modify data are
   called read/write, <firstterm>master</> or <firstterm>primary</> servers.
   Servers that track changes in the master are called <firstterm>standby</>
-  or <firstterm>slave</> servers. A standby server that cannot be connected
+  or <firstterm>secondary</> servers. A standby server that cannot be connected
   to until it is promoted to a master server is called a <firstterm>warm
   standby</> server, and one that can accept connections and serves read-only
   queries is called a <firstterm>hot standby</> server.

doc/src/sgml/ref/pgupgrade.sgml

@@ -483,7 +483,7 @@ pg_upgrade.exe
 
       <para>
        From a directory that is above the old and new database cluster
-       directories, run this for each slave:
+       directories, run this for each standby:
 
 <programlisting>
 rsync --archive --delete --hard-links --size-only old_pgdata new_pgdata remote_dir
@@ -517,7 +517,7 @@ rsync --archive --delete --hard-links --size-only old_pgdata new_pgdata remote_d
       <para>
        Configure the servers for log shipping.  (You do not need to run
        <function>pg_start_backup()</> and <function>pg_stop_backup()</>
-       or take a file system backup as the slaves are still synchronized
+       or take a file system backup as the standbys are still synchronized
        with the master.)
       </para>
      </step>

src/backend/access/transam/commit_ts.c

@@ -621,7 +621,7 @@ CommitTsParameterChange(bool newvalue, bool oldvalue)
  *
  * The reason why this SLRU needs separate activation/deactivation functions is
  * that it can be enabled/disabled during start and the activation/deactivation
- * on master is propagated to slave via replay. Other SLRUs don't have this
+ * on master is propagated to standby via replay. Other SLRUs don't have this
  * property and they can be just initialized during normal startup.
  *
  * This is in charge of creating the currently active segment, if it's not

src/backend/access/transam/multixact.c

@@ -939,7 +939,7 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 
 	debug_elog3(DEBUG2, "GetNew: for %d xids", nmembers);
 
-	/* safety check, we should never get this far in a HS slave */
+	/* safety check, we should never get this far in a HS standby */
 	if (RecoveryInProgress())
 		elog(ERROR, "cannot assign MultiXactIds during recovery");
 

src/backend/access/transam/varsup.c

@@ -67,7 +67,7 @@ GetNewTransactionId(bool isSubXact)
 		return BootstrapTransactionId;
 	}
 
-	/* safety check, we should never get this far in a HS slave */
+	/* safety check, we should never get this far in a HS standby */
 	if (RecoveryInProgress())
 		elog(ERROR, "cannot assign TransactionIds during recovery");
 
@@ -468,7 +468,7 @@ GetNewObjectId(void)
 {
 	Oid			result;
 
-	/* safety check, we should never get this far in a HS slave */
+	/* safety check, we should never get this far in a HS standby */
 	if (RecoveryInProgress())
 		elog(ERROR, "cannot assign OIDs during recovery");
 

src/backend/catalog/namespace.c

@@ -3802,10 +3802,10 @@ InitTempTableNamespace(void)
 						get_database_name(MyDatabaseId))));
 
 	/*
-	 * Do not allow a Hot Standby slave session to make temp tables.  Aside
+	 * Do not allow a Hot Standby session to make temp tables.  Aside
 	 * from problems with modifying the system catalogs, there is a naming
 	 * conflict: pg_temp_N belongs to the session with BackendId N on the
-	 * master, not to a slave session with the same BackendId.  We should not
+	 * master, not to a hot standby session with the same BackendId.  We should not
 	 * be able to get here anyway due to XactReadOnly checks, but let's just
 	 * make real sure.  Note that this also backstops various operations that
 	 * allow XactReadOnly transactions to modify temp tables; they'd need

src/backend/commands/variable.c

@@ -472,8 +472,8 @@ show_log_timezone(void)
  * We allow idempotent changes (r/w -> r/w and r/o -> r/o) at any time, and
  * we also always allow changes from read-write to read-only.  However,
  * read-only may be changed to read-write only when in a top-level transaction
- * that has not yet taken an initial snapshot.  Can't do it in a hot standby
- * slave, either.
+ * that has not yet taken an initial snapshot.  Can't do it in a hot standby,
+ * either.
  *
  * If we are not in a transaction at all, just allow the change; it means
  * nothing since XactReadOnly will be reset by the next StartTransaction().

src/backend/executor/execMain.c

@@ -759,8 +759,8 @@ ExecCheckRTEPermsModified(Oid relOid, Oid userid, Bitmapset *modifiedCols,
  * unless we're in parallel mode, in which case don't even allow writes
  * to temp tables.
  *
- * Note: in a Hot Standby slave this would need to reject writes to temp
- * tables just as we do in parallel mode; but an HS slave can't have created
+ * Note: in a Hot Standby this would need to reject writes to temp
+ * tables just as we do in parallel mode; but an HS standby can't have created
  * any temp tables in the first place, so no need to check that.
  */
 static void