SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56553333d311091c26c89077d2bb1f0cab3c5b12339ba6dbfa1c0ee237174dcd' 
  AND token = 'SOV8Ghyf35UJFEIK1MOKohe52WtzCmmsTo7gLIlLBAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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