Index Rebuild and Reorganize

Question

How we can identify that we have to rebuild and reorganize the indexes in sqlserver. i mean to say that percentage is acceptable of fragmentation for rebuild the indexes.

for example below status report:

index_id    avg_page_space_used_in_percent  avg_fragmentation_in_percent    index_level     record_count    page_count  fragment_count  avg_record_size_in_bytes
1   99.47111441 0   0   300000  2231    2   57.888
1   89.55707932 0   1   2231    4   2   11
1   0.617741537 0   2   4   1   1   11
4   99.72704472 0.113895216 0   300000  878 4   21.629
4   80.40214974 0   1   878 4   2   27.657
4   1.383741043 0   2   4   1   1   26.5
5   99.71136644 0   0   300000  1236    4   31.259
5   85.67899679 0   1   1236    7   2   37.286
5   3.261675315 0   2   7   1   1   36

please let me know and i would like know criteria,when this action required.

Answer 1

act acording to this link it explains how and when