SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac54a90b31e8087918cf8ea337731330db570266a2ebe2b3ed48ef8ce8ed0330' 
  AND token = 'lcTRb7xL2DXFy0avL4/UCHcgPI41w3r5IPDsKfyyO74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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