SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1815c6480c2d4ec25643237d736ae274372ba5918466d0d6c0340935fe21ffc9' 
  AND token = 'MFujVjePGabHlz5ZSD8kvG5fl5IqLg2zM5PI9rfCTHI=' 
  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"
    }
  }
}