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
- hydraulic potential
- hydraulic-powered,mechanical-operated puppet theatre
- hydraulic power transfer unit
- hydraulic power transmission
- hydraulic press
- hydraulic pressure-reducing valve
- hydraulic properties of discontinuity
- hydraulic properties of rock
- hydraulic protection for pipeline crossing the large loess gully
- Hydraulic Prototype Observation
- hydraulic ram
- hydraulic ram pump
- hydraulic resistance
- hydraulics
- hydraulic seal
- hydraulic sealing effect
- hydraulic servo-motor
- hydraulic servomotor
- hydraulic servo-system
- hydraulics experiment
- hydraulic ship Lift
- hydraulic shovel
- hydraulic simulation of fishway
- hydraulics of pipe flow
- hydraulic spinning wheel