SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0198d1eb5f1edf372dbcbc7a380e4893ec14b01ce66ff230558bea7975d243c0' 
  AND token = 'WZuYwxqO3ziaDTk9NygKVtUs+gjlYGPk2PAWu/jxpTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}