SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dd3a937c23e45d2f81ab554ff61404a2bf291b2cef32070dae56643375a1150' 
  AND token = 'HsSXE+VNBNTq5zVNly52XGqdSB/FfEtO0/JLViYBJcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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