SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e4a7a554c0a82f4b8b85f0c2d82bfe689008956b4a998aae2351520a286afd4' 
  AND token = 'orm4fRg+74BnPR172fqV0ngxLfFa6HD+pT2gHnbQM/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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