I'm new in SEO, I have a web application can let user post their own page. I have use PHP to update sitemap.xml (daily.)
How often do Google and Bing come back to crawl my sitemap? Do I need to do any setting in webmaster tool? How can I tell Google and Bing to come back and crawl my sitemap?
I cannot answer for Bing, but for Google, the best thing to do is wait. Google will not recheck your sitemap every time they visit, but depending upon how often it has changed in the past, Google will assign a TTL (time to live) style value to your sitemap that dictates how often to check the sitemap for changes. If your sitemap changes often, then Google will check it more often. My sitemap changes between every one to two weeks. That is exactly how often Google checks for changes. However, I do warn you, if you try and refresh or resubmit your sitemap using Google Webmaster Tools, you will interrupt this process and unfortunately, you will end up waiting longer. Another warning. If your sitemap indicates that it has changed and Google fetches it and there is no change, it will not update the TTL for that file. So even if I regenerate my sitemap daily, but there is no actual change, then the modify date cannot be trusted and Google will only update the TTL according to when it actually sees a change. For a period, this may be largely unsettled, but will become more regular as Google takes more chances. Keep in mind that Google checks for additions or changes, but may ignore dates and variables that are associated with regenerating the sitemap. So, for example, if no pages are added, Google may see your sitemap as not having changed.
For Bing you can hit the following url (http://www.bing.com/ping?sitemap=http://yoursite.com/sitemap.xml) and it will re-read your sitemap. I'm not sure long it takes to update their search results after that.
You'll probably want to join both Bing's and Google's Webmaster Tools to get more details on the status of the indexing.
I don't know for bing but For google, I am going to tell you a tool by which you will index pages in google within some MINUTES!!!.Following are steps to index your pages.
1.Go to DASHBOARD of your website is Google webmaster tools.
2.Now, go to Crawl-->Fetch as Google
3.Then enter URL of the page you want to index.
4.Now,Click on Fetch and then after loading page,Check the status and if it is Complete then press Submit to index
5.Now new box will opened, Click on Crawl only this URL(You will get 500 submissions per month)
6.Now wait for some time and search for your page in Google.You will find it...
I hope this will Help you As i also use it for my blog
