ご返信いただきありがとうございます。

/shop/data/logs/error.log を確認したところ、
以下のようなエラーが出ていました。

長くなりますがログを貼り付けます。

＜以下、error.log＞

2891 2022/07/06 09:20:11 [/shop/products/list.php] Warning(E_WARNING): in_array() expects parameter 2 to be arr ay, object given on [/var/www/html/hogehoge/httpdocs/shop/data/class/plugin/SC_Plugin_Util.php(38)] from 111.101.74.217

2892 2022/07/06 09:20:11 [/shop/products/list.php] Warning(E_WARNING): count(): Parameter must be an array or a n object that implements Countable on [/var/www/html/hogehoge/httpdocs/shop/data/class/helper/SC_Helper_ PageLayout.php(382)] from 111.101.74.217

2893 2022/07/06 09:20:11 [/shop/products/list.php] Fatal error(E_USER_ERROR): DB処理でエラーが発生しました。

2894 SQL: [PREPARE mdb2_statement_mysqli_23566b796e0581ed09a3cf6d9f9adac93f9c2d672a FROM 'SELECT p roduct_id ,product_code_min ,product_code_max ,name ,c omment1 ,comment2 ,comment3 ,main_list_comment ,main_i mage ,main_list_image ,price01_min ,price01_max ,price 02_min ,price02_max ,stock_min ,stock_max ,stock_unlim ited_min ,stock_unlimited_max ,deliv_date_id ,status , del_flg ,update_date FROM ( SELECT dtb_pro ducts.* ,T4.product_code_min ,T4.product_code_max ,T4.price01_min ,T4.price01_max ,T4.price02_min ,T4.price02_max ,T4.stock_min ,T4.stock_max ,T4.stock_unlimited_min ,T4.stock_unlimited_max ,T4 .point_rate ,T4.deliv_fee ,T4.class_count , dtb_maker.name AS maker_name FROM dtb_products INNER JOIN ( SELECT product_id, MIN(product_code) AS product_code_min, MAX(product_code) AS product_code_max, MIN(price01 ) AS price01_min, MAX(price01) AS price01_max, M IN(price02) AS price02_min, MAX(price02) AS price02_max, MIN(stock) AS stock_min, MAX(stock) AS stock_max, MIN(stock_unlimited) AS stock_unlimited_min, MAX(stock_unlimited) AS stock_unlimited_max, MAX(point_rate) AS point_rate, MAX(deliv_fee) AS deliv_fee, COUNT(*) as class_count FROM dtb_products_class WHERE del_flg = 0 GROUP BY product_id ) AS T4 ON dtb_products.product_id = T4.produ ct_id LEFT JOIN dtb_maker ON dtb_products.maker_id = dtb_mak er.maker_id ) AS alldtl WHERE alldtl.product_id IN (?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,? ,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?) AND alldtl.del_flg = 0 ']

2895 PlaceHolder: [array (
2896 0 => '4823',
2897 1 => '4822',
2898 2 => '4821',
2899 3 => '4820',
2900 4 => '4819',
2901 5 => '4818',
2902 6 => '4817',
2903 7 => '4816',
2904 8 => '4815',
2905 9 => '4814',
2906 10 => '4813',
2907 11 => '4812',
2908 12 => '4811',
2909 13 => '4810',
2910 14 => '4809',
2911 15 => '4808',
2912 16 => '4807',
2913 17 => '4806',
2914 18 => '4805',
2915 19 => '4804',
12 => '4811',
13 => '4810',
14 => '4809',
15 => '4808',
16 => '4807',
17 => '4806',
18 => '4805',
19 => '4804',
20 => '4803',
21 => '4802',
22 => '4801',
23 => '4800',
24 => '4799',
25 => '4798',
26 => '4797',
27 => '4796',
28 => '4795',
29 => '4794',
30 => '4793',
31 => '4792',
32 => '4791',
33 => '4790',
34 => '4789',
35 => '4788',
)]
MDB2 Error: unknown error
_doQuery: [Error message: Could not execute statement]
[Last executed query: EXECUTE mdb2_statement_mysqli_23566b796e0581ed09a3cf6d9f9adac93f9c2d672a USING @0, @1, @2, @3, @4, @5, @6, @7, @8, @9, @10, @11, @12, @13, @14, @15, @16, @17, @18, @19, @20, @21, @22, @23, @24, @25, @26, @27, @28, @29, @30, @31, @32, @33, @34, @35]
[Native code: 1030]
[Native message: Got error 28 from storage engine]
on [/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Query.php(1095)] from 111.101.74.217
customer_id =
/var/www/html/hogehoge/httpdocs/shop/products/list.php(29): LC_Page_Products_List_Ex->process
/var/www/html/hogehoge/httpdocs/shop/data/class_extends/page_extends/products/LC_Page_Products_List_Ex.php(54): LC_Page_Products_List->process
/var/www/html/hogehoge/httpdocs/shop/data/class/pages/products/LC_Page_Products_List.php(89): LC_Page_Products_List->action
/var/www/html/hogehoge/httpdocs/shop/data/class/pages/products/LC_Page_Products_List.php(298): LC_Page_Products_List->lfGetProductsList
/var/www/html/hogehoge/httpdocs/shop/data/class/pages/products/LC_Page_Products_List.php(552): SC_Product->getListByProductIds
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Product.php(176): SC_Product->lists
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Product.php(150): SC_Query->select
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Query.php(176): SC_Query->getAll
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Query.php(309): SC_Query->execute
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Query.php(1056): SC_Query->error
/var/www/html/hogehoge/httpdocs/shop/data/class/SC_Query.php(1095): trigger_error

＜ここまでがerror.log＞


ここから何かわかりそうでしょうか。
過去の投稿でキャッシュクリアのことがあったので
以下のファイルを消してみたのですが、
ひきつづきシステムエラーが出ています。

/shop/data/Smarty/templates_c
/shop/data/cache

何かヒントでもいただけると嬉しいです。
恐れ入りますがよろしくお願いいたします。