SELECT 
  cscart_bm_snapping.grid_id as grid_id, 
  cscart_bm_snapping.block_id as block_id, 
  IFNULL(
    dynamic_object_content.content, 
    default_content.content
  ) as content, 
  IFNULL(
    dynamic_object_content.object_id, 
    default_content.object_id
  ) AS object_id, 
  IFNULL(
    dynamic_object_content.object_type, 
    default_content.object_type
  ) AS object_type, 
  cscart_bm_block_statuses.object_ids as object_ids, 
  cscart_bm_snapping.*, 
  cscart_bm_blocks.*, 
  cscart_bm_blocks_descriptions.* 
FROM 
  cscart_bm_snapping 
  LEFT JOIN cscart_bm_blocks ON cscart_bm_blocks.block_id = cscart_bm_snapping.block_id 
  LEFT JOIN cscart_bm_block_statuses ON cscart_bm_snapping.snapping_id = cscart_bm_block_statuses.snapping_id 
  AND cscart_bm_block_statuses.object_type LIKE 'categories' 
  LEFT JOIN cscart_bm_blocks_descriptions ON cscart_bm_blocks.block_id = cscart_bm_blocks_descriptions.block_id 
  LEFT JOIN cscart_bm_blocks_content AS default_content ON cscart_bm_blocks.block_id = default_content.block_id 
  AND cscart_bm_blocks_descriptions.lang_code = default_content.lang_code 
  AND default_content.snapping_id = 0 
  AND default_content.object_id = 0 
  AND default_content.object_type like '' 
  LEFT JOIN cscart_bm_blocks_content AS dynamic_object_content ON cscart_bm_blocks.block_id = dynamic_object_content.block_id 
  AND cscart_bm_blocks_descriptions.lang_code = dynamic_object_content.lang_code 
  AND dynamic_object_content.object_id = 273 
  AND dynamic_object_content.object_type like 'categories' 
WHERE 
  cscart_bm_snapping.grid_id IN (
    79, 80, 81, 82, 83, 84, 85, 86, 89, 92, 97, 
    90, 91, 93, 98, 99, 94, 149, 95, 96, 110, 
    111, 112
  ) 
  AND cscart_bm_blocks_descriptions.lang_code = 'en' 
  AND cscart_bm_blocks.company_id = 1 
ORDER BY 
  cscart_bm_snapping.order, 
  cscart_bm_snapping.block_id

Query time 0.00267

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_bm_block_statuses",
          "access_type": "system",
          "possible_keys": ["snapping_id"],
          "rows": 0,
          "filtered": 0,
          "const_row_not_found": true
        }
      },
      {
        "read_sorted_file": {
          "filesort": {
            "sort_key": "cscart_bm_snapping.`order`, cscart_bm_snapping.block_id",
            "table": {
              "table_name": "cscart_bm_snapping",
              "access_type": "range",
              "possible_keys": ["grid_id"],
              "key": "grid_id",
              "key_length": "4",
              "used_key_parts": ["grid_id"],
              "rows": 29,
              "filtered": 100,
              "index_condition": "cscart_bm_snapping.grid_id in (79,80,81,82,83,84,85,86,89,92,97,90,91,93,98,99,94,149,95,96,110,111,112)"
            }
          }
        }
      },
      {
        "table": {
          "table_name": "cscart_bm_blocks",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "4",
          "used_key_parts": ["block_id"],
          "ref": ["u358358020_main.cscart_bm_snapping.block_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "cscart_bm_blocks.company_id = 1"
        }
      },
      {
        "table": {
          "table_name": "cscart_bm_blocks_descriptions",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "10",
          "used_key_parts": ["block_id", "lang_code"],
          "ref": ["u358358020_main.cscart_bm_snapping.block_id", "const"],
          "rows": 1,
          "filtered": 100,
          "index_condition": "cscart_bm_blocks_descriptions.lang_code = 'en'"
        }
      },
      {
        "table": {
          "table_name": "default_content",
          "access_type": "ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "18",
          "used_key_parts": ["block_id", "snapping_id", "lang_code", "object_id"],
          "ref": [
            "u358358020_main.cscart_bm_snapping.block_id",
            "const",
            "u358358020_main.cscart_bm_blocks_descriptions.lang_code",
            "const"
          ],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "trigcond(default_content.object_type like '')"
        }
      },
      {
        "table": {
          "table_name": "dynamic_object_content",
          "access_type": "ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "4",
          "used_key_parts": ["block_id"],
          "ref": ["u358358020_main.cscart_bm_snapping.block_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "trigcond(dynamic_object_content.lang_code = cscart_bm_blocks_descriptions.lang_code and dynamic_object_content.object_id = 273 and dynamic_object_content.object_type like 'categories')"
        }
      }
    ]
  }
}

Result

grid_id block_id content object_id object_type object_ids snapping_id wrapper user_class order status type properties company_id storefront_id lang_code name
80 3 a:1:{s:4:"menu";s:1:"1";} 0 85 top-quick-links 0 D menu a:2:{s:8:"template";s:26:"blocks/menu/text_links.tpl";s:18:"show_items_in_line";s:1:"Y";} 1 1 en Quick links
81 4 0 86 blocks/wrappers/onclick_dropdown.tpl top-my-account 0 A my_account a:1:{s:8:"template";s:21:"blocks/my_account.tpl";} 1 1 en
82 5 0 87 top-logo 0 A template a:2:{s:8:"template";s:32:"blocks/static_templates/logo.tpl";s:11:"enable_link";s:1:"Y";} 1 1 en Logo
84 6 0 89 0 A call_request a:1:{s:8:"template";s:44:"addons/call_requests/blocks/call_request.tpl";} 1 1 en Call Request
110 10 0 113 0 A breadcrumbs a:1:{s:8:"template";s:22:"common/breadcrumbs.tpl";} 1 1 en Breadcrumbs
96 17 a:1:{s:7:"content";s:342:" <ul id="about_cs_cart_links"> <li class="ty-footer-menu__item"><a href="{"pages.view?page_id=1"|fn_url}">Our team</a></li> <li class="ty-footer-menu__item"><a href="{"pages.view?page_id=3"|fn_url}">Privacy policy</a></li> </ul>";} 0 99 blocks/wrappers/footer_general.tpl footer-no-wysiwyg 0 A safe_smarty_block a:1:{s:8:"template";s:28:"blocks/safe_smarty_block.tpl";} 1 1 en About us
111 31 a:1:{s:5:"items";a:1:{s:7:"filling";s:8:"manually";}} 0 115 blocks/wrappers/sidebox_important.tpl 0 A product_filters a:1:{s:8:"template";s:48:"blocks/product_filters/for_category/original.tpl";} 1 1 en Product filters
111 32 a:1:{s:5:"items";a:2:{s:7:"filling";s:15:"recent_products";s:5:"limit";s:1:"3";}} 0 116 blocks/wrappers/sidebox_important.tpl 0 A products a:3:{s:8:"template";s:40:"blocks/products/products_small_items.tpl";s:11:"item_number";s:1:"N";s:23:"hide_add_to_cart_button";s:1:"Y";} 1 1 en Recently Viewed
86 55 a:1:{s:5:"items";a:3:{s:7:"filling";s:13:"full_tree_cat";s:18:"parent_category_id";s:0:"";s:7:"sort_by";s:8:"position";}} 0 91 0 A categories a:3:{s:8:"template";s:52:"blocks/categories/categories_dropdown_horizontal.tpl";s:30:"dropdown_second_level_elements";s:2:"12";s:29:"dropdown_third_level_elements";s:1:"6";} 1 1 en Main menu
110 66 a:1:{s:5:"items";a:1:{s:7:"filling";s:8:"manually";}} 0 114 0 A product_filters a:1:{s:8:"template";s:56:"blocks/product_filters/for_category/selected_filters.tpl";} 1 1 en Selected product filters
112 67 a:1:{s:5:"items";a:2:{s:7:"filling";s:8:"manually";s:8:"item_ids";s:1:"8";}} 0 117 ty-holiday-gift-banner 0 D banners a:1:{s:8:"template";s:34:"addons/banners/blocks/original.tpl";} 1 1 en Gift banner
149 73 a:1:{s:7:"content";s:661:"<ul id="demo_store_links"> <li class="ty-footer-menu__item"><a href="/cold-drinks-juices">Cold Drinks & Juices</a></li> <li class="ty-footer-menu__item"><a href="/snacks-munchies">Snacks & Munchies</a></li> <li class="ty-footer-menu__item"><a href="/breakfast-instant-food">Breakfast & Instant food</a></li> <li class="ty-footer-menu__item"><a href="/dairy-bread">Dairy & Bread</a></li> <li class="ty-footer-menu__item"><a href="/atta-rice-dal">Atta, Rice & Dal</a></li> <li class="ty-footer-menu__item"><a href="/masala-oils-more">Masala, Oils & More</a></li> <li class="ty-footer-menu__item"><a href="/bakery-biscuits">Bakery & Biscuits</a></li> </ul>";} 0 169 blocks/wrappers/footer_general.tpl footer-no-wysiwyg 0 A safe_smarty_block a:1:{s:8:"template";s:28:"blocks/safe_smarty_block.tpl";} 1 1 en Categories
85 8 0 90 top-cart-content 1 A cart_content a:5:{s:8:"template";s:23:"blocks/cart_content.tpl";s:22:"display_bottom_buttons";s:1:"Y";s:20:"display_delete_icons";s:1:"Y";s:19:"products_links_type";s:5:"thumb";s:20:"generate_block_title";s:1:"Y";} 1 1 en Cart content
112 11 0 118 blocks/wrappers/mainbox_general.tpl 1 A main 1 1 en Main Content
93 57 0 96 blocks/wrappers/footer_general.tpl 1 A template a:1:{s:8:"template";s:44:"blocks/static_templates/my_account_links.tpl";} 1 1 en My Account
94 58 a:1:{s:7:"content";s:504:"<ul id="demo_store_links"> <li class="ty-footer-menu__item"><a href="{"pages.view?page_id=2"|fn_url}">About us</a></li> <li class="ty-footer-menu__item"><a href="{"pages.view?page_id=30"|fn_url}">Contact us</a></li> <li class="ty-footer-menu__item"><a href="{"gift_certificates.add"|fn_url}">Gift certificates</a></li> <li class="ty-footer-menu__item"><a href="{"sitemap.view"|fn_url}">Sitemap</a></li> <li class="ty-footer-menu__item"><a href="{"pages.view?page_id=42"|fn_url}">Blog</a></li> </ul>";} 0 97 blocks/wrappers/footer_general.tpl footer-no-wysiwyg 1 A safe_smarty_block a:1:{s:8:"template";s:28:"blocks/safe_smarty_block.tpl";} 1 1 en My Store
81 71 0 167 hidden-tablet hidden-desktop 1 A cart_content a:4:{s:8:"template";s:23:"blocks/cart_content.tpl";s:22:"display_bottom_buttons";s:1:"Y";s:20:"display_delete_icons";s:1:"Y";s:19:"products_links_type";s:5:"thumb";} 1 1 en Cart Mobile
80 72 0 168 hidden-tablet hidden-desktop 1 D call_request a:1:{s:8:"template";s:44:"addons/call_requests/blocks/call_request.tpl";} 1 1 en Call For mobile
83 7 0 88 top-search 2 A template a:1:{s:8:"template";s:34:"blocks/static_templates/search.tpl";} 1 1 en Search
91 13 a:1:{s:7:"content";s:683:"<div class="ty-social-link-block"><h3 class="ty-social-link__title">{__("get_social")}</h3> <div class="ty-social-link facebook"> <a href="http://www.facebook.com"><span class="ty-icon ty-icon-facebook"></span>Facebook</a> </div> <div class="ty-social-link instagram"> <a href="https://www.instagram.com"><span class="ty-icon ty-icon-instagram"></span>Instagram</a> </div> <div class="ty-social-link twitter"> <a href="https://twitter.com"><span class="ty-icon ty-icon-twitter"></span>Twitter</a> </div> <div class="ty-social-link youtube"> <a href="https://www.youtube.com/user/cscartvideos"><span class="ty-icon ty-icon-youtube"></span>Youtube</a> </div></div> ";} 0 95 2 A safe_smarty_block a:1:{s:8:"template";s:28:"blocks/safe_smarty_block.tpl";} 1 1 en Social links
99 19 0 100 2 A template a:1:{s:8:"template";s:41:"blocks/static_templates/payment_icons.tpl";} 1 1 en Payment icons
79 54 a:1:{s:4:"text";s:0:"";} 0 83 top-languages 2 A languages a:3:{s:8:"template";s:20:"blocks/languages.tpl";s:6:"format";s:4:"name";s:14:"dropdown_limit";s:1:"0";} 1 1 en Languages
98 56 0 94 2 A template a:1:{s:8:"template";s:56:"addons/newsletters/blocks/static_templates/subscribe.tpl";} 1 1 en Subscribe
95 59 a:1:{s:7:"content";s:757:" <ul id="customer_service_links"> <li class="ty-footer-menu__item"><a href="{"orders.search"|fn_url}" rel="nofollow">About your order</a></li> {if $addons.wishlist && $addons.wishlist.status == 'A'} <li class="ty-footer-menu__item"><a href="{"wishlist.view"|fn_url}" rel="nofollow">Wishlist</a></li> {/if} {if $settings.General.enable_compare_products == 'Y'} <li class="ty-footer-menu__item"><a href="{"product_features.compare"|fn_url}" rel="nofollow">Comparison list</a></li> {/if} </ul>";} 0 98 blocks/wrappers/footer_general.tpl footer-no-wysiwyg 2 A safe_smarty_block a:1:{s:8:"template";s:28:"blocks/safe_smarty_block.tpl";} 1 1 en Customer Service
79 2 a:1:{s:4:"text";s:0:"";} 0 84 top-currencies 3 A currencies a:3:{s:8:"template";s:21:"blocks/currencies.tpl";s:6:"format";s:6:"symbol";s:14:"dropdown_limit";s:1:"3";} 1 1 en Currencies