SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68128a13cbeed08e15d3afcad730e509bbf2aefdfabec0b81c24d6275dfe874d' 
  AND token = 'YmXvqxWMRI6ficHJzFz0/NMCjXW57/X6z6Ib9Wnq8hM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}