SELECT 
  category_id 
FROM 
  cscart_categories 
WHERE 
  ab__lc_landing = 'Y'

Query time 0.00165

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "41.62"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "ALL",
      "rows_examined_per_scan": 383,
      "rows_produced_per_join": 38,
      "filtered": "10.00",
      "cost_info": {
        "read_cost": "37.79",
        "eval_cost": "3.83",
        "prefix_cost": "41.62",
        "data_read_per_join": "202K"
      },
      "used_columns": [
        "category_id",
        "ab__lc_landing"
      ],
      "attached_condition": "(`test_uchur_k`.`cscart_categories`.`ab__lc_landing` = 'Y')"
    }
  }
}