SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4398e7fa93718abe55ad86670379d4dfe5da0949c95fbdd1a22cbf963035878c' 
  AND token = 'tS+tHeuZIseCwEVyvR4T8MifpMT0laPMnanLKIR09hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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