SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88be517fea63d9392784bcefd415c3741048e4468815986df32f109ff26f1728' 
  AND token = 'T8pOF4jeSTy/uZTcXLTFN7L6AN2Ff9pCTy+pYVVy3po=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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