Use appendStringInfoString and appendPQExpBufferStr where possible

This changes various places where appendPQExpBuffer was used in places
where it was possible to use appendPQExpBufferStr, and likewise for
appendStringInfo and appendStringInfoString.  This is really just a
stylistic improvement, but there are also small performance gains to be
had from doing this.

Discussion: http://postgr.es/m/CAKJS1f9P=M-3ULmPvr8iCno8yvfDViHibJjpriHU8+SXUgeZ=w@mail.gmail.com

25 files changed, 195 insertions, 195 deletions

diff --git a/contrib/postgres_fdw/deparse.c b/contrib/postgres_fdw/deparse.c
index 6da4c834bf8..b951b11592e 100644
--- a/contrib/postgres_fdw/deparse.c
+++ b/contrib/postgres_fdw/deparse.c
@@ -1531,7 +1531,7 @@ deparseFromExprForRel(StringInfo buf, PlannerInfo *root, RelOptInfo *foreignrel,
 			{
 				Assert(fpinfo->jointype == JOIN_INNER);
 				Assert(fpinfo->joinclauses == NIL);
-				appendStringInfo(buf, "%s", join_sql_o.data);
+				appendStringInfoString(buf, join_sql_o.data);
 				return;
 			}
 		}
@@ -1552,7 +1552,7 @@ deparseFromExprForRel(StringInfo buf, PlannerInfo *root, RelOptInfo *foreignrel,
 			{
 				Assert(fpinfo->jointype == JOIN_INNER);
 				Assert(fpinfo->joinclauses == NIL);
-				appendStringInfo(buf, "%s", join_sql_i.data);
+				appendStringInfoString(buf, join_sql_i.data);
 				return;
 			}
 		}
@@ -1861,7 +1861,7 @@ deparseDirectUpdateSql(StringInfo buf, PlannerInfo *root,
 	{
 		List	   *ignore_conds = NIL;
 
-		appendStringInfo(buf, " FROM ");
+		appendStringInfoString(buf, " FROM ");
 		deparseFromExprForRel(buf, root, foreignrel, true, rtindex,
 							  &ignore_conds, params_list);
 		remote_conds = list_concat(remote_conds, ignore_conds);
@@ -1944,7 +1944,7 @@ deparseDirectDeleteSql(StringInfo buf, PlannerInfo *root,
 	{
 		List	   *ignore_conds = NIL;
 
-		appendStringInfo(buf, " USING ");
+		appendStringInfoString(buf, " USING ");
 		deparseFromExprForRel(buf, root, foreignrel, true, rtindex,
 							  &ignore_conds, params_list);
 		remote_conds = list_concat(remote_conds, ignore_conds);
diff --git a/contrib/sepgsql/database.c b/contrib/sepgsql/database.c
index 0cffb69c76b..8edd3df643c 100644
--- a/contrib/sepgsql/database.c
+++ b/contrib/sepgsql/database.c
@@ -63,7 +63,7 @@ sepgsql_database_post_create(Oid databaseId, const char *dtemplate)
 	 * check db_database:{getattr} permission
 	 */
 	initStringInfo(&audit_name);
-	appendStringInfo(&audit_name, "%s", quote_identifier(dtemplate));
+	appendStringInfoString(&audit_name, quote_identifier(dtemplate));
 	sepgsql_avc_check_perms_label(tcontext,
 								  SEPG_CLASS_DB_DATABASE,
 								  SEPG_DB_DATABASE__GETATTR,
@@ -101,8 +101,8 @@ sepgsql_database_post_create(Oid databaseId, const char *dtemplate)
 	 * check db_database:{create} permission
 	 */
 	resetStringInfo(&audit_name);
-	appendStringInfo(&audit_name, "%s",
-					 quote_identifier(NameStr(datForm->datname)));
+	appendStringInfoString(&audit_name,
+						   quote_identifier(NameStr(datForm->datname)));
 	sepgsql_avc_check_perms_label(ncontext,
 								  SEPG_CLASS_DB_DATABASE,
 								  SEPG_DB_DATABASE__CREATE,
diff --git a/contrib/sepgsql/label.c b/contrib/sepgsql/label.c
index 0b0d21c7f5d..1d17d5a0c04 100644
--- a/contrib/sepgsql/label.c
+++ b/contrib/sepgsql/label.c
@@ -676,7 +676,7 @@ quote_object_name(const char *src1, const char *src2,
 	if (src1)
 	{
 		temp = quote_identifier(src1);
-		appendStringInfo(&result, "%s", temp);
+		appendStringInfoString(&result, temp);
 		if (src1 != temp)
 			pfree((void *) temp);
 	}
diff --git a/contrib/sepgsql/selinux.c b/contrib/sepgsql/selinux.c
index fbc044e818c..bc2be8427af 100644
--- a/contrib/sepgsql/selinux.c
+++ b/contrib/sepgsql/selinux.c
@@ -702,7 +702,7 @@ sepgsql_audit_log(bool denied,
 			appendStringInfo(&buf, " %s", av_name);
 		}
 	}
-	appendStringInfo(&buf, " }");
+	appendStringInfoString(&buf, " }");
 
 	/*
 	 * Call external audit module, if loaded
diff --git a/contrib/test_decoding/test_decoding.c b/contrib/test_decoding/test_decoding.c
index 33955a478ed..a0ded67b9aa 100644
--- a/contrib/test_decoding/test_decoding.c
+++ b/contrib/test_decoding/test_decoding.c
@@ -518,9 +518,9 @@ pg_decode_truncate(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
 		|| change->data.truncate.cascade)
 	{
 		if (change->data.truncate.restart_seqs)
-			appendStringInfo(ctx->out, " restart_seqs");
+			appendStringInfoString(ctx->out, " restart_seqs");
 		if (change->data.truncate.cascade)
-			appendStringInfo(ctx->out, " cascade");
+			appendStringInfoString(ctx->out, " cascade");
 	}
 	else
 		appendStringInfoString(ctx->out, " (no-flags)");
diff --git a/src/backend/access/rmgrdesc/heapdesc.c b/src/backend/access/rmgrdesc/heapdesc.c
index eff529f9908..f25ebcda999 100644
--- a/src/backend/access/rmgrdesc/heapdesc.c
+++ b/src/backend/access/rmgrdesc/heapdesc.c
@@ -86,9 +86,9 @@ heap_desc(StringInfo buf, XLogReaderState *record)
 		int			i;
 
 		if (xlrec->flags & XLH_TRUNCATE_CASCADE)
-			appendStringInfo(buf, "cascade ");
+			appendStringInfoString(buf, "cascade ");
 		if (xlrec->flags & XLH_TRUNCATE_RESTART_SEQS)
-			appendStringInfo(buf, "restart_seqs ");
+			appendStringInfoString(buf, "restart_seqs ");
 		appendStringInfo(buf, "nrelids %u relids", xlrec->nrelids);
 		for (i = 0; i < xlrec->nrelids; i++)
 			appendStringInfo(buf, " %u", xlrec->relids[i]);
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 92969636b75..dff2ed3f978 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -822,7 +822,7 @@ ExplainPrintJIT(ExplainState *es, int jit_flags,
 		if (for_workers)
 			appendStringInfo(es->str, "JIT for worker %u:\n", worker_num);
 		else
-			appendStringInfo(es->str, "JIT:\n");
+			appendStringInfoString(es->str, "JIT:\n");
 		es->indent += 1;
 
 		ExplainPropertyInteger("Functions", NULL, ji->created_functions, es);
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index b9fdd99db8e..71adf700fc8 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -1723,7 +1723,7 @@ pg_get_partkeydef_worker(Oid relid, int prettyFlags,
 	{
 		case PARTITION_STRATEGY_HASH:
 			if (!attrsOnly)
-				appendStringInfo(&buf, "HASH");
+				appendStringInfoString(&buf, "HASH");
 			break;
 		case PARTITION_STRATEGY_LIST:
 			if (!attrsOnly)
diff --git a/src/bin/pg_basebackup/streamutil.c b/src/bin/pg_basebackup/streamutil.c
index 79f17e4089f..8d8ac11b664 100644
--- a/src/bin/pg_basebackup/streamutil.c
+++ b/src/bin/pg_basebackup/streamutil.c
@@ -500,19 +500,19 @@ CreateReplicationSlot(PGconn *conn, const char *slot_name, const char *plugin,
 	/* Build query */
 	appendPQExpBuffer(query, "CREATE_REPLICATION_SLOT \"%s\"", slot_name);
 	if (is_temporary)
-		appendPQExpBuffer(query, " TEMPORARY");
+		appendPQExpBufferStr(query, " TEMPORARY");
 	if (is_physical)
 	{
-		appendPQExpBuffer(query, " PHYSICAL");
+		appendPQExpBufferStr(query, " PHYSICAL");
 		if (reserve_wal)
-			appendPQExpBuffer(query, " RESERVE_WAL");
+			appendPQExpBufferStr(query, " RESERVE_WAL");
 	}
 	else
 	{
 		appendPQExpBuffer(query, " LOGICAL \"%s\"", plugin);
 		if (PQserverVersion(conn) >= 100000)
 			/* pg_recvlogical doesn't use an exported snapshot, so suppress */
-			appendPQExpBuffer(query, " NOEXPORT_SNAPSHOT");
+			appendPQExpBufferStr(query, " NOEXPORT_SNAPSHOT");
 	}
 
 	res = PQexec(conn, query->data);
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index dfb6c19f5a4..a10bc8d545b 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -1481,14 +1481,14 @@ pgwin32_CommandLine(bool registration)
 		appendPQExpBuffer(cmdLine, " -e \"%s\"", event_source);
 
 	if (registration && do_wait)
-		appendPQExpBuffer(cmdLine, " -w");
+		appendPQExpBufferStr(cmdLine, " -w");
 
 	/* Don't propagate a value from an environment variable. */
 	if (registration && wait_seconds_arg && wait_seconds != DEFAULT_WAIT)
 		appendPQExpBuffer(cmdLine, " -t %d", wait_seconds);
 
 	if (registration && silent_mode)
-		appendPQExpBuffer(cmdLine, " -s");
+		appendPQExpBufferStr(cmdLine, " -s");
 
 	if (post_opts)
 	{
diff --git a/src/bin/pg_dump/dumputils.c b/src/bin/pg_dump/dumputils.c
index ef8b53cd091..2c49b0ff367 100644
--- a/src/bin/pg_dump/dumputils.c
+++ b/src/bin/pg_dump/dumputils.c
@@ -425,7 +425,7 @@ buildDefaultACLCommands(const char *type, const char *nspname,
 
 	if (strlen(initacls) != 0 || strlen(initracls) != 0)
 	{
-		appendPQExpBuffer(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(true);\n");
+		appendPQExpBufferStr(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(true);\n");
 		if (!buildACLCommands("", NULL, NULL, type,
 							  initacls, initracls, owner,
 							  prefix->data, remoteVersion, sql))
@@ -433,7 +433,7 @@ buildDefaultACLCommands(const char *type, const char *nspname,
 			destroyPQExpBuffer(prefix);
 			return false;
 		}
-		appendPQExpBuffer(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(false);\n");
+		appendPQExpBufferStr(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(false);\n");
 	}
 
 	if (!buildACLCommands("", NULL, NULL, type,
diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
index 40c77af540c..0f40328310b 100644
--- a/src/bin/pg_dump/pg_backup_archiver.c
+++ b/src/bin/pg_dump/pg_backup_archiver.c
@@ -554,8 +554,8 @@ RestoreArchive(Archive *AHX)
 							 */
 							if (strncmp(dropStmt, "ALTER TABLE", 11) == 0)
 							{
-								appendPQExpBuffer(ftStmt,
-												  "ALTER TABLE IF EXISTS");
+								appendPQExpBufferStr(ftStmt,
+													 "ALTER TABLE IF EXISTS");
 								dropStmt = dropStmt + 11;
 							}
 
@@ -4870,7 +4870,7 @@ CloneArchive(ArchiveHandle *AH)
 		 * any data to/from the database.
 		 */
 		initPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, PQdb(AH->connection));
 		pghost = PQhost(AH->connection);
 		pgport = PQport(AH->connection);
diff --git a/src/bin/pg_dump/pg_backup_db.c b/src/bin/pg_dump/pg_backup_db.c
index 8af5c7bebdb..9d33c86a3ba 100644
--- a/src/bin/pg_dump/pg_backup_db.c
+++ b/src/bin/pg_dump/pg_backup_db.c
@@ -149,7 +149,7 @@ _connectDB(ArchiveHandle *AH, const char *reqdb, const char *requser)
 	}
 
 	initPQExpBuffer(&connstr);
-	appendPQExpBuffer(&connstr, "dbname=");
+	appendPQExpBufferStr(&connstr, "dbname=");
 	appendConnStrVal(&connstr, newdb);
 
 	do
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 1cd25adb6cf..806fc78f048 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -1205,7 +1205,7 @@ setup_connection(Archive *AH, const char *dumpencoding,
 	{
 		PQExpBuffer query = createPQExpBuffer();
 
-		appendPQExpBuffer(query, "SET TRANSACTION SNAPSHOT ");
+		appendPQExpBufferStr(query, "SET TRANSACTION SNAPSHOT ");
 		appendStringLiteralConn(query, AH->sync_snapshot_id, conn);
 		ExecuteSqlStatement(AH, query->data);
 		destroyPQExpBuffer(query);
@@ -1315,8 +1315,8 @@ expand_schema_name_patterns(Archive *fout,
 
 	for (cell = patterns->head; cell; cell = cell->next)
 	{
-		appendPQExpBuffer(query,
-						  "SELECT oid FROM pg_catalog.pg_namespace n\n");
+		appendPQExpBufferStr(query,
+							 "SELECT oid FROM pg_catalog.pg_namespace n\n");
 		processSQLNamePattern(GetConnection(fout), query, cell->val, false,
 							  false, NULL, "n.nspname", NULL, NULL);
 
@@ -3733,7 +3733,7 @@ dumpPolicy(Archive *fout, PolicyInfo *polinfo)
 	if (polinfo->polwithcheck != NULL)
 		appendPQExpBuffer(query, " WITH CHECK (%s)", polinfo->polwithcheck);
 
-	appendPQExpBuffer(query, ";\n");
+	appendPQExpBufferStr(query, ";\n");
 
 	appendPQExpBuffer(delqry, "DROP POLICY %s", fmtId(polinfo->polname));
 	appendPQExpBuffer(delqry, " ON %s;\n", fmtQualifiedDumpable(tbinfo));
@@ -4560,7 +4560,7 @@ getNamespaces(Archive *fout, int *numNamespaces)
 						  init_acl_subquery->data,
 						  init_racl_subquery->data);
 
-		appendPQExpBuffer(query, ") ");
+		appendPQExpBufferStr(query, ") ");
 
 		destroyPQExpBuffer(acl_subquery);
 		destroyPQExpBuffer(racl_subquery);
@@ -5248,9 +5248,9 @@ getAccessMethods(Archive *fout, int *numAccessMethods)
 	query = createPQExpBuffer();
 
 	/* Select all access methods from pg_am table */
-	appendPQExpBuffer(query, "SELECT tableoid, oid, amname, amtype, "
-					  "amhandler::pg_catalog.regproc AS amhandler "
-					  "FROM pg_am");
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, amname, amtype, "
+						 "amhandler::pg_catalog.regproc AS amhandler "
+						 "FROM pg_am");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8128,10 +8128,10 @@ getTransforms(Archive *fout, int *numTransforms)
 
 	query = createPQExpBuffer();
 
-	appendPQExpBuffer(query, "SELECT tableoid, oid, "
-					  "trftype, trflang, trffromsql::oid, trftosql::oid "
-					  "FROM pg_transform "
-					  "ORDER BY 3,4");
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, "
+						 "trftype, trflang, trffromsql::oid, trftosql::oid "
+						 "FROM pg_transform "
+						 "ORDER BY 3,4");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -8255,55 +8255,55 @@ getTableAttrs(Archive *fout, TableInfo *tblinfo, int numTables)
 
 		resetPQExpBuffer(q);
 
-		appendPQExpBuffer(q,
-						  "SELECT\n"
-						  "a.attnum,\n"
-						  "a.attname,\n"
-						  "a.atttypmod,\n"
-						  "a.attstattarget,\n"
-						  "a.attstorage,\n"
-						  "t.typstorage,\n"
-						  "a.attnotnull,\n"
-						  "a.atthasdef,\n"
-						  "a.attisdropped,\n"
-						  "a.attlen,\n"
-						  "a.attalign,\n"
-						  "a.attislocal,\n"
-						  "pg_catalog.format_type(t.oid, a.atttypmod) AS atttypname,\n");
+		appendPQExpBufferStr(q,
+							 "SELECT\n"
+							 "a.attnum,\n"
+							 "a.attname,\n"
+							 "a.atttypmod,\n"
+							 "a.attstattarget,\n"
+							 "a.attstorage,\n"
+							 "t.typstorage,\n"
+							 "a.attnotnull,\n"
+							 "a.atthasdef,\n"
+							 "a.attisdropped,\n"
+							 "a.attlen,\n"
+							 "a.attalign,\n"
+							 "a.attislocal,\n"
+							 "pg_catalog.format_type(t.oid, a.atttypmod) AS atttypname,\n");
 
 		if (fout->remoteVersion >= 120000)
-			appendPQExpBuffer(q,
-							  "a.attgenerated,\n");
+			appendPQExpBufferStr(q,
+								 "a.attgenerated,\n");
 		else
-			appendPQExpBuffer(q,
-							  "'' AS attgenerated,\n");
+			appendPQExpBufferStr(q,
+								 "'' AS attgenerated,\n");
 
 		if (fout->remoteVersion >= 110000)
-			appendPQExpBuffer(q,
-							  "CASE WHEN a.atthasmissing AND NOT a.attisdropped "
-							  "THEN a.attmissingval ELSE null END AS attmissingval,\n");
+			appendPQExpBufferStr(q,
+								 "CASE WHEN a.atthasmissing AND NOT a.attisdropped "
+								 "THEN a.attmissingval ELSE null END AS attmissingval,\n");
 		else
-			appendPQExpBuffer(q,
-							  "NULL AS attmissingval,\n");
+			appendPQExpBufferStr(q,
+								 "NULL AS attmissingval,\n");
 
 		if (fout->remoteVersion >= 100000)
-			appendPQExpBuffer(q,
-							  "a.attidentity,\n");
+			appendPQExpBufferStr(q,
+								 "a.attidentity,\n");
 		else
-			appendPQExpBuffer(q,
-							  "'' AS attidentity,\n");
+			appendPQExpBufferStr(q,
+								 "'' AS attidentity,\n");
 
 		if (fout->remoteVersion >= 90200)
-			appendPQExpBuffer(q,
-							  "pg_catalog.array_to_string(ARRAY("
-							  "SELECT pg_catalog.quote_ident(option_name) || "
-							  "' ' || pg_catalog.quote_literal(option_value) "
-							  "FROM pg_catalog.pg_options_to_table(attfdwoptions) "
-							  "ORDER BY option_name"
-							  "), E',\n    ') AS attfdwoptions,\n");
+			appendPQExpBufferStr(q,
+								 "pg_catalog.array_to_string(ARRAY("
+								 "SELECT pg_catalog.quote_ident(option_name) || "
+								 "' ' || pg_catalog.quote_literal(option_value) "
+								 "FROM pg_catalog.pg_options_to_table(attfdwoptions) "
+								 "ORDER BY option_name"
+								 "), E',\n    ') AS attfdwoptions,\n");
 		else
-			appendPQExpBuffer(q,
-							  "'' AS attfdwoptions,\n");
+			appendPQExpBufferStr(q,
+								 "'' AS attfdwoptions,\n");
 
 		if (fout->remoteVersion >= 90100)
 		{
@@ -8312,20 +8312,20 @@ getTableAttrs(Archive *fout, TableInfo *tblinfo, int numTables)
 			 * collation is different from their type's default, we use a CASE
 			 * here to suppress uninteresting attcollations cheaply.
 			 */
-			appendPQExpBuffer(q,
-							  "CASE WHEN a.attcollation <> t.typcollation "
-							  "THEN a.attcollation ELSE 0 END AS attcollation,\n");
+			appendPQExpBufferStr(q,
+								 "CASE WHEN a.attcollation <> t.typcollation "
+								 "THEN a.attcollation ELSE 0 END AS attcollation,\n");
 		}
 		else
-			appendPQExpBuffer(q,
-							  "0 AS attcollation,\n");
+			appendPQExpBufferStr(q,
+								 "0 AS attcollation,\n");
 
 		if (fout->remoteVersion >= 90000)
-			appendPQExpBuffer(q,
-							  "array_to_string(a.attoptions, ', ') AS attoptions\n");
+			appendPQExpBufferStr(q,
+								 "array_to_string(a.attoptions, ', ') AS attoptions\n");
 		else
-			appendPQExpBuffer(q,
-							  "'' AS attoptions\n");
+			appendPQExpBufferStr(q,
+								 "'' AS attoptions\n");
 
 		/* need left join here to not fail on dropped columns ... */
 		appendPQExpBuffer(q,
@@ -12331,7 +12331,7 @@ dumpTransform(Archive *fout, TransformInfo *transform)
 	if (transform->trftosql)
 	{
 		if (transform->trffromsql)
-			appendPQExpBuffer(defqry, ", ");
+			appendPQExpBufferStr(defqry, ", ");
 
 		if (tosqlFuncInfo)
 		{
@@ -12349,7 +12349,7 @@ dumpTransform(Archive *fout, TransformInfo *transform)
 			pg_log_warning("bogus value in pg_transform.trftosql field");
 	}
 
-	appendPQExpBuffer(defqry, ");\n");
+	appendPQExpBufferStr(defqry, ");\n");
 
 	appendPQExpBuffer(labelq, "TRANSFORM FOR %s LANGUAGE %s",
 					  transformType, lanname);
@@ -12724,10 +12724,10 @@ dumpAccessMethod(Archive *fout, AccessMethodInfo *aminfo)
 	switch (aminfo->amtype)
 	{
 		case AMTYPE_INDEX:
-			appendPQExpBuffer(q, "TYPE INDEX ");
+			appendPQExpBufferStr(q, "TYPE INDEX ");
 			break;
 		case AMTYPE_TABLE:
-			appendPQExpBuffer(q, "TYPE TABLE ");
+			appendPQExpBufferStr(q, "TYPE TABLE ");
 			break;
 		default:
 			pg_log_warning("invalid type \"%c\" of access method \"%s\"",
@@ -13433,23 +13433,23 @@ dumpCollation(Archive *fout, CollInfo *collinfo)
 	qcollname = pg_strdup(fmtId(collinfo->dobj.name));
 
 	/* Get collation-specific details */
-	appendPQExpBuffer(query, "SELECT ");
+	appendPQExpBufferStr(query, "SELECT ");
 
 	if (fout->remoteVersion >= 100000)
-		appendPQExpBuffer(query,
-						  "collprovider, "
-						  "collversion, ");
+		appendPQExpBufferStr(query,
+							 "collprovider, "
+							 "collversion, ");
 	else
-		appendPQExpBuffer(query,
-						  "'c' AS collprovider, "
-						  "NULL AS collversion, ");
+		appendPQExpBufferStr(query,
+							 "'c' AS collprovider, "
+							 "NULL AS collversion, ");
 
 	if (fout->remoteVersion >= 120000)
-		appendPQExpBuffer(query,
-						  "collisdeterministic, ");
+		appendPQExpBufferStr(query,
+							 "collisdeterministic, ");
 	else
-		appendPQExpBuffer(query,
-						  "true AS collisdeterministic, ");
+		appendPQExpBufferStr(query,
+							 "true AS collisdeterministic, ");
 
 	appendPQExpBuffer(query,
 					  "collcollate, "
@@ -13665,7 +13665,7 @@ format_aggregate_signature(AggInfo *agginfo, Archive *fout, bool honor_quotes)
 		appendPQExpBufferStr(&buf, agginfo->aggfn.dobj.name);
 
 	if (agginfo->aggfn.nargs == 0)
-		appendPQExpBuffer(&buf, "(*)");
+		appendPQExpBufferStr(&buf, "(*)");
 	else
 	{
 		appendPQExpBufferChar(&buf, '(');
@@ -14883,13 +14883,13 @@ dumpACL(Archive *fout, CatalogId objCatId, DumpId objDumpId,
 	 */
 	if (strlen(initacls) != 0 || strlen(initracls) != 0)
 	{
-		appendPQExpBuffer(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(true);\n");
+		appendPQExpBufferStr(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(true);\n");
 		if (!buildACLCommands(name, subname, nspname, type,
 							  initacls, initracls, owner,
 							  "", fout->remoteVersion, sql))
 			fatal("could not parse initial GRANT ACL list (%s) or initial REVOKE ACL list (%s) for object \"%s\" (%s)",
 				  initacls, initracls, name, type);
-		appendPQExpBuffer(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(false);\n");
+		appendPQExpBufferStr(sql, "SELECT pg_catalog.binary_upgrade_set_record_init_privs(false);\n");
 	}
 
 	if (!buildACLCommands(name, subname, nspname, type,
@@ -16591,7 +16591,7 @@ dumpConstraint(Archive *fout, ConstraintInfo *coninfo)
 			}
 
 			if (indxinfo->indnkeyattrs < indxinfo->indnattrs)
-				appendPQExpBuffer(q, ") INCLUDE (");
+				appendPQExpBufferStr(q, ") INCLUDE (");
 
 			for (k = indxinfo->indnkeyattrs; k < indxinfo->indnattrs; k++)
 			{
@@ -16988,9 +16988,9 @@ dumpSequence(Archive *fout, TableInfo *tbinfo)
 						  "ALTER COLUMN %s ADD GENERATED ",
 						  fmtId(owning_tab->attnames[tbinfo->owning_col - 1]));
 		if (owning_tab->attidentity[tbinfo->owning_col - 1] == ATTRIBUTE_IDENTITY_ALWAYS)
-			appendPQExpBuffer(query, "ALWAYS");
+			appendPQExpBufferStr(query, "ALWAYS");
 		else if (owning_tab->attidentity[tbinfo->owning_col - 1] == ATTRIBUTE_IDENTITY_BY_DEFAULT)
-			appendPQExpBuffer(query, "BY DEFAULT");
+			appendPQExpBufferStr(query, "BY DEFAULT");
 		appendPQExpBuffer(query, " AS IDENTITY (\n    SEQUENCE NAME %s\n",
 						  fmtQualifiedDumpable(tbinfo));
 	}
diff --git a/src/bin/pg_dump/pg_dumpall.c b/src/bin/pg_dump/pg_dumpall.c
index 66e0a610ab7..158c0c74b20 100644
--- a/src/bin/pg_dump/pg_dumpall.c
+++ b/src/bin/pg_dump/pg_dumpall.c
@@ -1432,8 +1432,8 @@ expand_dbname_patterns(PGconn *conn,
 
 	for (SimpleStringListCell *cell = patterns->head; cell; cell = cell->next)
 	{
-		appendPQExpBuffer(query,
-						  "SELECT datname FROM pg_catalog.pg_database n\n");
+		appendPQExpBufferStr(query,
+							 "SELECT datname FROM pg_catalog.pg_database n\n");
 		processSQLNamePattern(conn, query, cell->val, false,
 							  false, NULL, "datname", NULL, NULL);
 
diff --git a/src/bin/pg_upgrade/dump.c b/src/bin/pg_upgrade/dump.c
index 0ffe171a055..c1429fe4bfb 100644
--- a/src/bin/pg_upgrade/dump.c
+++ b/src/bin/pg_upgrade/dump.c
@@ -42,7 +42,7 @@ generate_old_dump(void)
 					escaped_connstr;
 
 		initPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, old_db->db_name);
 		initPQExpBuffer(&escaped_connstr);
 		appendShellString(&escaped_connstr, connstr.data);
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 6263f8a7798..66e1aec011a 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -2992,7 +2992,7 @@ do_connect(enum trivalue reuse_previous_specification,
 	if (!dbname && reuse_previous)
 	{
 		initPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, PQdb(o_conn));
 		dbname = connstr.data;
 		/* has_connection_string=true would be a dead store */
@@ -4576,7 +4576,7 @@ lookup_object_oid(EditableObjectType obj_type, const char *desc,
 			 */
 			appendPQExpBufferStr(query, "SELECT ");
 			appendStringLiteralConn(query, desc, pset.db);
-			appendPQExpBuffer(query, "::pg_catalog.regclass::pg_catalog.oid");
+			appendPQExpBufferStr(query, "::pg_catalog.regclass::pg_catalog.oid");
 			break;
 	}
 
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index 0e0af5f942c..8b4cd53631c 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -2115,8 +2115,8 @@ describeOneTableDetails(const char *schemaname,
 						  "  pg_catalog.pg_get_expr(c.relpartbound, inhrelid)");
 		/* If verbose, also request the partition constraint definition */
 		if (verbose)
-			appendPQExpBuffer(&buf,
-							  ",\n  pg_catalog.pg_get_partition_constraintdef(inhrelid)");
+			appendPQExpBufferStr(&buf,
+								 ",\n  pg_catalog.pg_get_partition_constraintdef(inhrelid)");
 		appendPQExpBuffer(&buf,
 						  "\nFROM pg_catalog.pg_class c"
 						  " JOIN pg_catalog.pg_inherits i"
@@ -2203,9 +2203,9 @@ describeOneTableDetails(const char *schemaname,
 								 "  false AS condeferrable, false AS condeferred,\n");
 
 		if (pset.sversion >= 90400)
-			appendPQExpBuffer(&buf, "i.indisreplident,\n");
+			appendPQExpBufferStr(&buf, "i.indisreplident,\n");
 		else
-			appendPQExpBuffer(&buf, "false AS indisreplident,\n");
+			appendPQExpBufferStr(&buf, "false AS indisreplident,\n");
 
 		appendPQExpBuffer(&buf, "  a.amname, c2.relname, "
 						  "pg_catalog.pg_get_expr(i.indpred, i.indrelid, true)\n"
@@ -2263,7 +2263,7 @@ describeOneTableDetails(const char *schemaname,
 				appendPQExpBufferStr(&tmpbuf, _(", initially deferred"));
 
 			if (strcmp(indisreplident, "t") == 0)
-				appendPQExpBuffer(&tmpbuf, _(", replica identity"));
+				appendPQExpBufferStr(&tmpbuf, _(", replica identity"));
 
 			printTableAddFooter(&cont, tmpbuf.data);
 			add_tablespace_footer(&cont, tableinfo.relkind,
@@ -2374,7 +2374,7 @@ describeOneTableDetails(const char *schemaname,
 						appendPQExpBufferStr(&buf, " INVALID");
 
 					if (strcmp(PQgetvalue(result, i, 10), "t") == 0)
-						appendPQExpBuffer(&buf, " REPLICA IDENTITY");
+						appendPQExpBufferStr(&buf, " REPLICA IDENTITY");
 
 					printTableAddFooter(&cont, buf.data);
 
@@ -2457,8 +2457,8 @@ describeOneTableDetails(const char *schemaname,
 								  oid);
 
 				if (pset.sversion >= 120000)
-					appendPQExpBuffer(&buf, "     AND conparentid = 0\n");
-				appendPQExpBuffer(&buf, "ORDER BY conname");
+					appendPQExpBufferStr(&buf, "     AND conparentid = 0\n");
+				appendPQExpBufferStr(&buf, "ORDER BY conname");
 			}
 
 			result = PSQLexec(buf.data);
@@ -2556,11 +2556,11 @@ describeOneTableDetails(const char *schemaname,
 		{
 			printfPQExpBuffer(&buf, "SELECT pol.polname,");
 			if (pset.sversion >= 100000)
-				appendPQExpBuffer(&buf,
-								  " pol.polpermissive,\n");
+				appendPQExpBufferStr(&buf,
+									 " pol.polpermissive,\n");
 			else
-				appendPQExpBuffer(&buf,
-								  " 't' as polpermissive,\n");
+				appendPQExpBufferStr(&buf,
+									 " 't' as polpermissive,\n");
 			appendPQExpBuffer(&buf,
 							  "  CASE WHEN pol.polroles = '{0}' THEN NULL ELSE pg_catalog.array_to_string(array(select rolname from pg_catalog.pg_roles where oid = any (pol.polroles) order by 1),',') END,\n"
 							  "  pg_catalog.pg_get_expr(pol.polqual, pol.polrelid),\n"
@@ -2608,7 +2608,7 @@ describeOneTableDetails(const char *schemaname,
 								  PQgetvalue(result, i, 0));
 
 				if (*(PQgetvalue(result, i, 1)) == 'f')
-					appendPQExpBuffer(&buf, " AS RESTRICTIVE");
+					appendPQExpBufferStr(&buf, " AS RESTRICTIVE");
 
 				if (!PQgetisnull(result, i, 5))
 					appendPQExpBuffer(&buf, " FOR %s",
@@ -2913,12 +2913,12 @@ describeOneTableDetails(const char *schemaname,
 						   "t.tgconstraint <> 0 AS tgisinternal" :
 						   "false AS tgisinternal"), oid);
 		if (pset.sversion >= 110000)
-			appendPQExpBuffer(&buf, "(NOT t.tgisinternal OR (t.tgisinternal AND t.tgenabled = 'D') \n"
-							  "    OR EXISTS (SELECT 1 FROM pg_catalog.pg_depend WHERE objid = t.oid \n"
-							  "        AND refclassid = 'pg_catalog.pg_trigger'::pg_catalog.regclass))");
+			appendPQExpBufferStr(&buf, "(NOT t.tgisinternal OR (t.tgisinternal AND t.tgenabled = 'D') \n"
+								 "    OR EXISTS (SELECT 1 FROM pg_catalog.pg_depend WHERE objid = t.oid \n"
+								 "        AND refclassid = 'pg_catalog.pg_trigger'::pg_catalog.regclass))");
 		else if (pset.sversion >= 90000)
 			/* display/warn about disabled internal triggers */
-			appendPQExpBuffer(&buf, "(NOT t.tgisinternal OR (t.tgisinternal AND t.tgenabled = 'D'))");
+			appendPQExpBufferStr(&buf, "(NOT t.tgisinternal OR (t.tgisinternal AND t.tgenabled = 'D'))");
 		else if (pset.sversion >= 80300)
 			appendPQExpBufferStr(&buf, "(t.tgconstraint = 0 OR (t.tgconstraint <> 0 AND t.tgenabled = 'D'))");
 		else
@@ -3935,33 +3935,33 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose)
 	{
 		if (pset.sversion < 120000)
 		{
-			appendPQExpBuffer(&buf,
-							  ",\n     LATERAL (WITH RECURSIVE d\n"
-							  "                AS (SELECT inhrelid AS oid, 1 AS level\n"
-							  "                      FROM pg_catalog.pg_inherits\n"
-							  "                     WHERE inhparent = c.oid\n"
-							  "                    UNION ALL\n"
-							  "                    SELECT inhrelid, level + 1\n"
-							  "                      FROM pg_catalog.pg_inherits i\n"
-							  "                           JOIN d ON i.inhparent = d.oid)\n"
-							  "                SELECT pg_catalog.pg_size_pretty(sum(pg_catalog.pg_table_size("
-							  "d.oid))) AS tps,\n"
-							  "                       pg_catalog.pg_size_pretty(sum("
-							  "\n             CASE WHEN d.level = 1"
-							  " THEN pg_catalog.pg_table_size(d.oid) ELSE 0 END)) AS dps\n"
-							  "               FROM d) s");
+			appendPQExpBufferStr(&buf,
+								 ",\n     LATERAL (WITH RECURSIVE d\n"
+								 "                AS (SELECT inhrelid AS oid, 1 AS level\n"
+								 "                      FROM pg_catalog.pg_inherits\n"
+								 "                     WHERE inhparent = c.oid\n"
+								 "                    UNION ALL\n"
+								 "                    SELECT inhrelid, level + 1\n"
+								 "                      FROM pg_catalog.pg_inherits i\n"
+								 "                           JOIN d ON i.inhparent = d.oid)\n"
+								 "                SELECT pg_catalog.pg_size_pretty(sum(pg_catalog.pg_table_size("
+								 "d.oid))) AS tps,\n"
+								 "                       pg_catalog.pg_size_pretty(sum("
+								 "\n             CASE WHEN d.level = 1"
+								 " THEN pg_catalog.pg_table_size(d.oid) ELSE 0 END)) AS dps\n"
+								 "               FROM d) s");
 		}
 		else
 		{
 			/* PostgreSQL 12 has pg_partition_tree function */
-			appendPQExpBuffer(&buf,
-							  ",\n     LATERAL (SELECT pg_catalog.pg_size_pretty(sum("
-							  "\n                 CASE WHEN ppt.isleaf AND ppt.level = 1"
-							  "\n                      THEN pg_catalog.pg_table_size(ppt.relid)"
-							  " ELSE 0 END)) AS dps"
-							  ",\n                     pg_catalog.pg_size_pretty(sum("
-							  "pg_catalog.pg_table_size(ppt.relid))) AS tps"
-							  "\n              FROM pg_catalog.pg_partition_tree(c.oid) ppt) s");
+			appendPQExpBufferStr(&buf,
+								 ",\n     LATERAL (SELECT pg_catalog.pg_size_pretty(sum("
+								 "\n                 CASE WHEN ppt.isleaf AND ppt.level = 1"
+								 "\n                      THEN pg_catalog.pg_table_size(ppt.relid)"
+								 " ELSE 0 END)) AS dps"
+								 ",\n                     pg_catalog.pg_size_pretty(sum("
+								 "pg_catalog.pg_table_size(ppt.relid))) AS tps"
+								 "\n              FROM pg_catalog.pg_partition_tree(c.oid) ppt) s");
 		}
 	}
 
@@ -4003,7 +4003,7 @@ listPartitionedTables(const char *reltypes, const char *pattern, bool verbose)
 		return false;
 
 	initPQExpBuffer(&title);
-	appendPQExpBuffer(&title, "%s", tabletitle);
+	appendPQExpBufferStr(&title, tabletitle);
 
 	myopt.nullPrint = NULL;
 	myopt.title = title.data;
@@ -4567,8 +4567,8 @@ listSchemas(const char *pattern, bool verbose, bool showSystem)
 						  gettext_noop("Description"));
 	}
 
-	appendPQExpBuffer(&buf,
-					  "\nFROM pg_catalog.pg_namespace n\n");
+	appendPQExpBufferStr(&buf,
+						 "\nFROM pg_catalog.pg_namespace n\n");
 
 	if (!showSystem && !pattern)
 		appendPQExpBufferStr(&buf,
@@ -5768,10 +5768,10 @@ describePublications(const char *pattern)
 					  "  pg_catalog.pg_get_userbyid(pubowner) AS owner,\n"
 					  "  puballtables, pubinsert, pubupdate, pubdelete");
 	if (has_pubtruncate)
-		appendPQExpBuffer(&buf,
-						  ", pubtruncate");
-	appendPQExpBuffer(&buf,
-					  "\nFROM pg_catalog.pg_publication\n");
+		appendPQExpBufferStr(&buf,
+							 ", pubtruncate");
+	appendPQExpBufferStr(&buf,
+						 "\nFROM pg_catalog.pg_publication\n");
 
 	processSQLNamePattern(pset.db, &buf, pattern, false, false,
 						  NULL, "pubname", NULL,
diff --git a/src/bin/scripts/clusterdb.c b/src/bin/scripts/clusterdb.c
index 15fff91e161..ae0facd5a7f 100644
--- a/src/bin/scripts/clusterdb.c
+++ b/src/bin/scripts/clusterdb.c
@@ -254,7 +254,7 @@ cluster_all_databases(bool verbose, const char *maintenance_db,
 		}
 
 		resetPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, dbname);
 
 		cluster_one_database(connstr.data, verbose, NULL,
diff --git a/src/bin/scripts/reindexdb.c b/src/bin/scripts/reindexdb.c
index 3528de21e04..ca61348a0e5 100644
--- a/src/bin/scripts/reindexdb.c
+++ b/src/bin/scripts/reindexdb.c
@@ -420,7 +420,7 @@ reindex_all_databases(const char *maintenance_db,
 		}
 
 		resetPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, dbname);
 
 		reindex_one_database(NULL, connstr.data, REINDEX_DATABASE, host,
diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c
index df2a315f958..3bcd14b4dcf 100644
--- a/src/bin/scripts/vacuumdb.c
+++ b/src/bin/scripts/vacuumdb.c
@@ -477,16 +477,16 @@ vacuum_one_database(const char *dbname, vacuumingOptions *vacopts,
 
 		if (!tables_listed)
 		{
-			appendPQExpBuffer(&catalog_query,
-							  "WITH listed_tables (table_oid, column_list) "
-							  "AS (\n  VALUES (");
+			appendPQExpBufferStr(&catalog_query,
+								 "WITH listed_tables (table_oid, column_list) "
+								 "AS (\n  VALUES (");
 			tables_listed = true;
 		}
 		else
-			appendPQExpBuffer(&catalog_query, ",\n  (");
+			appendPQExpBufferStr(&catalog_query, ",\n  (");
 
 		appendStringLiteralConn(&catalog_query, just_table, conn);
-		appendPQExpBuffer(&catalog_query, "::pg_catalog.regclass, ");
+		appendPQExpBufferStr(&catalog_query, "::pg_catalog.regclass, ");
 
 		if (just_columns && just_columns[0] != '\0')
 			appendStringLiteralConn(&catalog_query, just_columns, conn);
@@ -500,24 +500,24 @@ vacuum_one_database(const char *dbname, vacuumingOptions *vacopts,
 
 	/* Finish formatting the CTE */
 	if (tables_listed)
-		appendPQExpBuffer(&catalog_query, "\n)\n");
+		appendPQExpBufferStr(&catalog_query, "\n)\n");
 
-	appendPQExpBuffer(&catalog_query, "SELECT c.relname, ns.nspname");
+	appendPQExpBufferStr(&catalog_query, "SELECT c.relname, ns.nspname");
 
 	if (tables_listed)
-		appendPQExpBuffer(&catalog_query, ", listed_tables.column_list");
+		appendPQExpBufferStr(&catalog_query, ", listed_tables.column_list");
 
-	appendPQExpBuffer(&catalog_query,
-					  " FROM pg_catalog.pg_class c\n"
-					  " JOIN pg_catalog.pg_namespace ns"
-					  " ON c.relnamespace OPERATOR(pg_catalog.=) ns.oid\n"
-					  " LEFT JOIN pg_catalog.pg_class t"
-					  " ON c.reltoastrelid OPERATOR(pg_catalog.=) t.oid\n");
+	appendPQExpBufferStr(&catalog_query,
+						 " FROM pg_catalog.pg_class c\n"
+						 " JOIN pg_catalog.pg_namespace ns"
+						 " ON c.relnamespace OPERATOR(pg_catalog.=) ns.oid\n"
+						 " LEFT JOIN pg_catalog.pg_class t"
+						 " ON c.reltoastrelid OPERATOR(pg_catalog.=) t.oid\n");
 
 	/* Used to match the tables listed by the user */
 	if (tables_listed)
-		appendPQExpBuffer(&catalog_query, " JOIN listed_tables"
-						  " ON listed_tables.table_oid OPERATOR(pg_catalog.=) c.oid\n");
+		appendPQExpBufferStr(&catalog_query, " JOIN listed_tables"
+							 " ON listed_tables.table_oid OPERATOR(pg_catalog.=) c.oid\n");
 
 	/*
 	 * If no tables were listed, filter for the relevant relation types.  If
@@ -527,9 +527,9 @@ vacuum_one_database(const char *dbname, vacuumingOptions *vacopts,
 	 */
 	if (!tables_listed)
 	{
-		appendPQExpBuffer(&catalog_query, " WHERE c.relkind OPERATOR(pg_catalog.=) ANY (array["
-						  CppAsString2(RELKIND_RELATION) ", "
-						  CppAsString2(RELKIND_MATVIEW) "])\n");
+		appendPQExpBufferStr(&catalog_query, " WHERE c.relkind OPERATOR(pg_catalog.=) ANY (array["
+							 CppAsString2(RELKIND_RELATION) ", "
+							 CppAsString2(RELKIND_MATVIEW) "])\n");
 		has_where = true;
 	}
 
@@ -568,7 +568,7 @@ vacuum_one_database(const char *dbname, vacuumingOptions *vacopts,
 	 * Execute the catalog query.  We use the default search_path for this
 	 * query for consistency with table lookups done elsewhere by the user.
 	 */
-	appendPQExpBuffer(&catalog_query, " ORDER BY c.relpages DESC;");
+	appendPQExpBufferStr(&catalog_query, " ORDER BY c.relpages DESC;");
 	executeCommand(conn, "RESET search_path;", progname, echo);
 	res = executeQuery(conn, catalog_query.data, progname, echo);
 	termPQExpBuffer(&catalog_query);
@@ -775,7 +775,7 @@ vacuum_all_databases(vacuumingOptions *vacopts,
 			for (i = 0; i < PQntuples(result); i++)
 			{
 				resetPQExpBuffer(&connstr);
-				appendPQExpBuffer(&connstr, "dbname=");
+				appendPQExpBufferStr(&connstr, "dbname=");
 				appendConnStrVal(&connstr, PQgetvalue(result, i, 0));
 
 				vacuum_one_database(connstr.data, vacopts,
@@ -792,7 +792,7 @@ vacuum_all_databases(vacuumingOptions *vacopts,
 		for (i = 0; i < PQntuples(result); i++)
 		{
 			resetPQExpBuffer(&connstr);
-			appendPQExpBuffer(&connstr, "dbname=");
+			appendPQExpBufferStr(&connstr, "dbname=");
 			appendConnStrVal(&connstr, PQgetvalue(result, i, 0));
 
 			vacuum_one_database(connstr.data, vacopts,
diff --git a/src/fe_utils/string_utils.c b/src/fe_utils/string_utils.c
index d5757becef2..8c3a603cf1d 100644
--- a/src/fe_utils/string_utils.c
+++ b/src/fe_utils/string_utils.c
@@ -624,10 +624,10 @@ appendPsqlMetaConnect(PQExpBuffer buf, const char *dbname)
 		PQExpBufferData connstr;
 
 		initPQExpBuffer(&connstr);
-		appendPQExpBuffer(&connstr, "dbname=");
+		appendPQExpBufferStr(&connstr, "dbname=");
 		appendConnStrVal(&connstr, dbname);
 
-		appendPQExpBuffer(buf, "-reuse-previous=on ");
+		appendPQExpBufferStr(buf, "-reuse-previous=on ");
 
 		/*
 		 * As long as the name does not contain a newline, SQL identifier
diff --git a/src/interfaces/libpq/fe-auth-scram.c b/src/interfaces/libpq/fe-auth-scram.c
index babdc061984..04ee43441c8 100644
--- a/src/interfaces/libpq/fe-auth-scram.c
+++ b/src/interfaces/libpq/fe-auth-scram.c
@@ -346,7 +346,7 @@ build_client_first_message(fe_scram_state *state)
 	if (strcmp(state->sasl_mechanism, SCRAM_SHA_256_PLUS_NAME) == 0)
 	{
 		Assert(conn->ssl_in_use);
-		appendPQExpBuffer(&buf, "p=tls-server-end-point");
+		appendPQExpBufferStr(&buf, "p=tls-server-end-point");
 	}
 #ifdef HAVE_PGTLS_GET_PEER_CERTIFICATE_HASH
 	else if (conn->ssl_in_use)
@@ -354,7 +354,7 @@ build_client_first_message(fe_scram_state *state)
 		/*
 		 * Client supports channel binding, but thinks the server does not.
 		 */
-		appendPQExpBuffer(&buf, "y");
+		appendPQExpBufferChar(&buf, 'y');
 	}
 #endif
 	else
@@ -362,7 +362,7 @@ build_client_first_message(fe_scram_state *state)
 		/*
 		 * Client does not support channel binding.
 		 */
-		appendPQExpBuffer(&buf, "n");
+		appendPQExpBufferChar(&buf, 'n');
 	}
 
 	if (PQExpBufferDataBroken(buf))
@@ -437,7 +437,7 @@ build_client_final_message(fe_scram_state *state)
 			return NULL;
 		}
 
-		appendPQExpBuffer(&buf, "c=");
+		appendPQExpBufferStr(&buf, "c=");
 
 		/* p=type,, */
 		cbind_header_len = strlen("p=tls-server-end-point,,");
@@ -475,10 +475,10 @@ build_client_final_message(fe_scram_state *state)
 	}
 #ifdef HAVE_PGTLS_GET_PEER_CERTIFICATE_HASH
 	else if (conn->ssl_in_use)
-		appendPQExpBuffer(&buf, "c=eSws");	/* base64 of "y,," */
+		appendPQExpBufferStr(&buf, "c=eSws");	/* base64 of "y,," */
 #endif
 	else
-		appendPQExpBuffer(&buf, "c=biws");	/* base64 of "n,," */
+		appendPQExpBufferStr(&buf, "c=biws");	/* base64 of "n,," */
 
 	if (PQExpBufferDataBroken(buf))
 		goto oom_error;
@@ -496,7 +496,7 @@ build_client_final_message(fe_scram_state *state)
 						   state->client_final_message_without_proof,
 						   client_proof);
 
-	appendPQExpBuffer(&buf, ",p=");
+	appendPQExpBufferStr(&buf, ",p=");
 	if (!enlargePQExpBuffer(&buf, pg_b64_enc_len(SCRAM_KEY_LEN)))
 		goto oom_error;
 	buf.len += pg_b64_encode((char *) client_proof,
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index c800d7921e3..d70cf1f9484 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -2772,8 +2772,8 @@ keep_going:						/* We will come back to here until there is
 				}
 				else if (!conn->gctx && conn->gssencmode[0] == 'r')
 				{
-					appendPQExpBuffer(&conn->errorMessage,
-									  libpq_gettext("GSSAPI encryption required, but was impossible (possibly no ccache, no server support, or using a local socket)\n"));
+					appendPQExpBufferStr(&conn->errorMessage,
+										 libpq_gettext("GSSAPI encryption required, but was impossible (possibly no ccache, no server support, or using a local socket)\n"));
 					goto error_return;
 				}
 #endif
diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c
index 467563d7a41..bbba48bc8b6 100644
--- a/src/interfaces/libpq/fe-protocol3.c
+++ b/src/interfaces/libpq/fe-protocol3.c
@@ -996,7 +996,7 @@ pqBuildErrorMessage3(PQExpBuffer msg, const PGresult *res,
 	/* If we couldn't allocate a PGresult, just say "out of memory" */
 	if (res == NULL)
 	{
-		appendPQExpBuffer(msg, libpq_gettext("out of memory\n"));
+		appendPQExpBufferStr(msg, libpq_gettext("out of memory\n"));
 		return;
 	}
 
@@ -1009,7 +1009,7 @@ pqBuildErrorMessage3(PQExpBuffer msg, const PGresult *res,
 		if (res->errMsg && res->errMsg[0])
 			appendPQExpBufferStr(msg, res->errMsg);
 		else
-			appendPQExpBuffer(msg, libpq_gettext("no error message available\n"));
+			appendPQExpBufferStr(msg, libpq_gettext("no error message available\n"));
 		return;
 	}