SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f82b198f7b242a14554ff6f239dfe956801d8fa96d3a3f78ea11644b73143d7' 
  AND token = 'hT/eGqKJ23pMYjofI2ca2QnVSzut10d2/JmxySbbwS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}