SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fa922738c03622eea220faf92b231f4976fc107050fb04b1470f99bf007882b' 
  AND token = 'RJqEFcUWr2IzzxOIzgiyBcIVgLwL4Bt7Z6jQD1EnlFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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