MDEV-25228 JSON_TABLE: Server crashes in Query_cache::unlink_table.

JSON_TABLE shojldn't be counted in the query_cache.

mysql-test/main/query_cache.result

@@ -2227,6 +2227,13 @@ SHOW STATUS LIKE 'Qcache_inserts';
 Variable_name	Value
 Qcache_inserts	0
 drop table t1;
+#
+# MDEV-25228 JSON_TABLE: Server crashes in Query_cache::unlink_table.
+#
+CREATE TABLE t (a INT);
+SELECT * FROM t JOIN JSON_TABLE('{}' , '$' COLUMNS(b FOR ORDINALITY)) AS jt;
+a	b
+DROP TABLE t;
 restore defaults
 SET GLOBAL query_cache_type= default;
 SET GLOBAL query_cache_size=@save_query_cache_size;

mysql-test/main/query_cache.test

@@ -1818,6 +1818,13 @@ select * from t1, json_table(t1.a, '$' columns (f varchar(20) path '$.a')) as jt
 SHOW STATUS LIKE 'Qcache_inserts';
 drop table t1;
 
+--echo #
+--echo # MDEV-25228 JSON_TABLE: Server crashes in Query_cache::unlink_table.
+--echo #
+CREATE TABLE t (a INT);
+SELECT * FROM t JOIN JSON_TABLE('{}' , '$' COLUMNS(b FOR ORDINALITY)) AS jt;
+DROP TABLE t;
+
 --echo restore defaults
 SET GLOBAL query_cache_type= default;
 SET GLOBAL query_cache_size=@save_query_cache_size;

sql/sql_cache.cc

@@ -4094,11 +4094,13 @@ Query_cache::process_and_count_tables(THD *thd, TABLE_LIST *tables_used,
       *tables_type|= HA_CACHE_TBL_NONTRANSACT;
       continue;
     }
-    if (tables_used->derived)
+    if (tables_used->derived || tables_used->table_function)
     {
       DBUG_PRINT("qcache", ("table: %s", tables_used->alias.str));
       table_count--;
-      DBUG_PRINT("qcache", ("derived table skipped"));
+      DBUG_PRINT("qcache", (tables_used->table_function ?
+                              "table function skipped" :
+                              "derived table skipped"));
       continue;
     }