diff --git a/src/backend/statistics/extended_stats_funcs.c b/src/backend/statistics/extended_stats_funcs.c
index 70393d3a904..ab748068225 100644
--- a/src/backend/statistics/extended_stats_funcs.c
+++ b/src/backend/statistics/extended_stats_funcs.c
@@ -886,7 +886,8 @@ key_in_expr_argnames(JsonbValue *key)
 	Assert(key->type == jbvString);
 	for (int i = 0; i < NUM_ATTRIBUTE_STATS_ELEMS; i++)
 	{
-		if (strncmp(extexprargname[i], key->val.string.val, key->val.string.len) == 0)
+		if (strlen(extexprargname[i]) == key->val.string.len &&
+			strncmp(extexprargname[i], key->val.string.val, key->val.string.len) == 0)
 			return true;
 	}
 	return false;
@@ -1592,7 +1593,7 @@ import_expressions(Relation pgsd, int numexprs,
 		ereport(WARNING,
 				errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				errmsg("could not parse \"%s\": incorrect number of elements (%d required)",
-					   argname, num_root_elements));
+					   argname, numexprs));
 		goto exprs_error;
 	}
 
@@ -1816,6 +1817,7 @@ pg_clear_extended_stats(PG_FUNCTION_ARGS)
 	 */
 	if (stxform->stxrelid != relid)
 	{
+		heap_freetuple(tup);
 		table_close(pg_stext, RowExclusiveLock);
 		ereport(WARNING,
 				errcode(ERRCODE_INVALID_PARAMETER_VALUE),
diff --git a/src/test/regress/expected/stats_import.out b/src/test/regress/expected/stats_import.out
index f421e83e232..183e68d65c2 100644
--- a/src/test/regress/expected/stats_import.out
+++ b/src/test/regress/expected/stats_import.out
@@ -2455,7 +2455,7 @@ WARNING:  could not parse "exprs": root-level array required
  f
 (1 row)
 
--- wrong number of exprs
+-- wrong number of exprs, too few
 SELECT pg_catalog.pg_restore_extended_stats(
   'schemaname', 'stats_import',
   'relname', 'test_clone',
@@ -2463,7 +2463,21 @@ SELECT pg_catalog.pg_restore_extended_stats(
   'statistics_name', 'test_stat_clone',
   'inherited', false,
   'exprs', '[ { "avg_width": "4" } ]'::jsonb);
-WARNING:  could not parse "exprs": incorrect number of elements (1 required)
+WARNING:  could not parse "exprs": incorrect number of elements (2 required)
+ pg_restore_extended_stats 
+---------------------------
+ f
+(1 row)
+
+-- wrong number of exprs, too many
+SELECT pg_catalog.pg_restore_extended_stats(
+  'schemaname', 'stats_import',
+  'relname', 'test_clone',
+  'statistics_schemaname', 'stats_import',
+  'statistics_name', 'test_stat_clone',
+  'inherited', false,
+  'exprs', '[ { "avg_width": "4" }, { "avg_width": "4" }, { "avg_width": "4" } ]'::jsonb);
+WARNING:  could not parse "exprs": incorrect number of elements (2 required)
  pg_restore_extended_stats 
 ---------------------------
  f
@@ -3256,6 +3270,20 @@ most_common_elems      | {-1,0,1,2,3}
 most_common_elem_freqs | {0.25,0.25,0.5,0.25,0.25,0.25,0.5,0.25}
 elem_count_histogram   | {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1.5}
 
+-- bad: exprs param which is a prefix of a valid key name
+SELECT pg_catalog.pg_restore_extended_stats(
+  'schemaname', 'stats_import',
+  'relname', 'test',
+  'statistics_schemaname', 'stats_import',
+  'statistics_name', 'test_stat_mcelem',
+  'inherited', false,
+  'exprs', '[{ "n": "-1" }]'::jsonb);
+WARNING:  could not import element in expression -1: invalid key name
+ pg_restore_extended_stats 
+---------------------------
+ f
+(1 row)
+
 -- ok: tsvector exceptions, test just the collation exceptions
 CREATE STATISTICS stats_import.test_stat_tsvec ON (length(name)), (to_tsvector(name)) FROM stats_import.test;
 SELECT pg_catalog.pg_restore_extended_stats(
diff --git a/src/test/regress/sql/stats_import.sql b/src/test/regress/sql/stats_import.sql
index c1bf55690a6..6064b7722da 100644
--- a/src/test/regress/sql/stats_import.sql
+++ b/src/test/regress/sql/stats_import.sql
@@ -1750,7 +1750,7 @@ SELECT pg_catalog.pg_restore_extended_stats(
   'statistics_name', 'test_stat_clone',
   'inherited', false,
   'exprs', '{ "avg_width": "4", "null_frac": "0" }'::jsonb);
--- wrong number of exprs
+-- wrong number of exprs, too few
 SELECT pg_catalog.pg_restore_extended_stats(
   'schemaname', 'stats_import',
   'relname', 'test_clone',
@@ -1758,6 +1758,14 @@ SELECT pg_catalog.pg_restore_extended_stats(
   'statistics_name', 'test_stat_clone',
   'inherited', false,
   'exprs', '[ { "avg_width": "4" } ]'::jsonb);
+-- wrong number of exprs, too many
+SELECT pg_catalog.pg_restore_extended_stats(
+  'schemaname', 'stats_import',
+  'relname', 'test_clone',
+  'statistics_schemaname', 'stats_import',
+  'statistics_name', 'test_stat_clone',
+  'inherited', false,
+  'exprs', '[ { "avg_width": "4" }, { "avg_width": "4" }, { "avg_width": "4" } ]'::jsonb);
 -- incorrect type of value: should be a string or a NULL.
 SELECT pg_catalog.pg_restore_extended_stats(
   'schemaname', 'stats_import',
@@ -2244,6 +2252,15 @@ WHERE e.statistics_schemaname = 'stats_import' AND
     e.inherited = false
 \gx
 
+-- bad: exprs param which is a prefix of a valid key name
+SELECT pg_catalog.pg_restore_extended_stats(
+  'schemaname', 'stats_import',
+  'relname', 'test',
+  'statistics_schemaname', 'stats_import',
+  'statistics_name', 'test_stat_mcelem',
+  'inherited', false,
+  'exprs', '[{ "n": "-1" }]'::jsonb);
+
 -- ok: tsvector exceptions, test just the collation exceptions
 CREATE STATISTICS stats_import.test_stat_tsvec ON (length(name)), (to_tsvector(name)) FROM stats_import.test;
 SELECT pg_catalog.pg_restore_extended_stats(