SELECT 
  tconnect_bm_snapping.grid_id as grid_id, 
  tconnect_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, 
  tconnect_bm_block_statuses.object_ids as object_ids, 
  tconnect_bm_snapping.*, 
  tconnect_bm_blocks.*, 
  tconnect_bm_blocks_descriptions.* 
FROM 
  tconnect_bm_snapping 
  LEFT JOIN tconnect_bm_blocks ON tconnect_bm_blocks.block_id = tconnect_bm_snapping.block_id 
  LEFT JOIN tconnect_bm_block_statuses ON tconnect_bm_snapping.snapping_id = tconnect_bm_block_statuses.snapping_id 
  AND tconnect_bm_block_statuses.object_type LIKE 'categories' 
  LEFT JOIN tconnect_bm_blocks_descriptions ON tconnect_bm_blocks.block_id = tconnect_bm_blocks_descriptions.block_id 
  LEFT JOIN tconnect_bm_blocks_content AS default_content ON tconnect_bm_blocks.block_id = default_content.block_id 
  AND tconnect_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 tconnect_bm_blocks_content AS dynamic_object_content ON tconnect_bm_blocks.block_id = dynamic_object_content.block_id 
  AND tconnect_bm_blocks_descriptions.lang_code = dynamic_object_content.lang_code 
  AND dynamic_object_content.object_id = 243 
  AND dynamic_object_content.object_type like 'categories' 
WHERE 
  tconnect_bm_snapping.grid_id IN (
    3015, 3016, 3017, 3018, 3019, 3020, 3041, 
    3046, 3042, 3043, 3044, 3045, 3047, 
    3048, 3051, 3052, 3053, 3054, 3055, 
    3056, 3057, 3058
  ) 
  AND tconnect_bm_blocks_descriptions.lang_code = 'en' 
ORDER BY 
  tconnect_bm_snapping.order, 
  tconnect_bm_snapping.block_id

Query time 0.00549

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 2.643939598,
    "nested_loop": [
      {
        "read_sorted_file": {
          "filesort": {
            "sort_key": "tconnect_bm_snapping.`order`, tconnect_bm_snapping.block_id",
            "table": {
              "table_name": "tconnect_bm_snapping",
              "access_type": "range",
              "possible_keys": ["grid_id"],
              "key": "grid_id",
              "key_length": "4",
              "used_key_parts": ["grid_id"],
              "loops": 1,
              "rows": 29,
              "cost": 0.050037867,
              "filtered": 100,
              "index_condition": "tconnect_bm_snapping.grid_id in (3015,3016,3017,3018,3019,3020,3041,3046,3042,3043,3044,3045,3047,3048,3051,3052,3053,3054,3055,3056,3057,3058)"
            }
          }
        }
      },
      {
        "table": {
          "table_name": "tconnect_bm_blocks",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "4",
          "used_key_parts": ["block_id"],
          "ref": ["tconnect.tconnect_bm_snapping.block_id"],
          "loops": 29,
          "rows": 1,
          "cost": 0.050756154,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "tconnect_bm_blocks_descriptions",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "10",
          "used_key_parts": ["block_id", "lang_code"],
          "ref": ["tconnect.tconnect_bm_snapping.block_id", "const"],
          "loops": 29,
          "rows": 1,
          "cost": 0.050960954,
          "filtered": 100,
          "index_condition": "tconnect_bm_blocks_descriptions.lang_code = 'en'"
        }
      },
      {
        "table": {
          "table_name": "tconnect_bm_block_statuses",
          "access_type": "ref",
          "possible_keys": ["snapping_id"],
          "key": "snapping_id",
          "key_length": "4",
          "used_key_parts": ["snapping_id"],
          "ref": ["tconnect.tconnect_bm_snapping.snapping_id"],
          "loops": 29,
          "rows": 1,
          "cost": 0.053178319,
          "filtered": 100,
          "attached_condition": "trigcond(tconnect_bm_snapping.snapping_id = tconnect_bm_block_statuses.snapping_id and tconnect_bm_block_statuses.object_type like 'categories')"
        }
      },
      {
        "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": [
            "tconnect.tconnect_bm_snapping.block_id",
            "const",
            "tconnect.tconnect_bm_blocks_descriptions.lang_code",
            "const"
          ],
          "loops": 29,
          "rows": 3,
          "cost": 0.130861601,
          "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": ["tconnect.tconnect_bm_snapping.block_id"],
          "loops": 105.415,
          "rows": 11,
          "cost": 1.511112471,
          "filtered": 100,
          "attached_condition": "trigcond(dynamic_object_content.lang_code = tconnect_bm_blocks_descriptions.lang_code and dynamic_object_content.object_id = 243 and dynamic_object_content.object_type like 'categories')"
        }
      }
    ]
  }
}