理学 数据库系统 释 query optimization 查询优化 查询优化旨在通过选择有效策略，对给定的关系表达式求值，使得查询代价最小。
数据库 数据库管理系统及其实现技术 释文 query optimization 查询优化
- Rupelian Stage
- Rupert Murdoch
- rupes
- Rupes Altai
- Rupes Boris
- Rupes Cauchy
- Rupes Kelvin
- Rupes Liebig
- Rupes Mercator
- Rupes Recta
- Rupes Toscanelli
- Ru Porcelain Museum of Ruzhou City
- Ruport’s Land
- Rupture
- rupture
- rupture and wreck of rotor
- rupture device
- rupture diaphragm
- rupture disk
- ruptured sinus of valsalva aneurysm
- ruptured wound of eyeball
- rupture of achilles tendon
- rupture of bladder in animals
- ruptures of earthquake sources
- rupture strength