反向建索引(三)
, then use the NOCACHE option or consider pre-generating the sequence numbers. If your application requires sequence number ordering but can tolerate gaps, then use CACHE andORDER to cache and order sequence numbers in
Oracle RAC. If your application requires ordered sequence numbers without gaps, then use NOCACHE andORDER. The NOCACHE and ORDER combination has the most negative effect on performance compared to other caching and ordering combinations.