SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe498149b09bca64ee95b89d2c8073bdeab781030bddc78c067d3506e45e14aa' 
  AND token = '92DX8LjBhjxUx4G31Rnd0gofmNP5zmdxXIkXHFf/F8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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