I submitted my site sitemap yesterday morning. About hundreds of index pages were reduced from Google by the end of yesterday afternoon. May be my site is a large one and the sitemap only contained a small part of it. Is it the reason that Google reduced pages? There are about half of one million pages on my site. And the number of indexed pages on Google is less than 7000 now. How to make google index my pages?
he did index your pages but you might have duplicate content so that does not show; your site map might not be perfect so you might want to work on that; wait for google to crawl again and then compare the results.
During "natural discovery", Google evaluates your pages and mainly works with "the good ones". It is very likely that your sitemap contains many URLs that offer little unique content... 1,000's of "login and return to this page" URLs which have different URLs, but the same "login below" message. Pages like 'make post', 'buy now', 'view cart' are very helpful for your visitors, but offer little or no value to the search engines. If these URLs have made it into your sitemap, then I could see where Google may reduce the number of URLs indexed, but there is a fairly easy fix... Remove these kinds of URLs from your sitemap. Your sitemap tool should allow you to exclude certain URLs from making their way into your sitemap.
Thank you for your advice. The site is large,if I divided the sitemap into several parts and remove all the unnecessary pages,is it a good idea to make google index my site?