理学 数据库系统 释 relational calculus 关系演算 一种抽象的关系数据语言，它通过数理逻辑中的谓词演算表达查询的要求。
数据库 数据库理论 释文 relational calculus 关系演算
- Wright function
- Wright Island
- Wright telescope
- wringing
- wringing number
- wrinkle
- wrinkled viburnum
- wrinkle recovery angle
- wrinkle ridge
- wrinkling
- wrist
- write
- write-after-erase
- write back
- write-back cache
- write broadcast
- write cycle
- write data line
- write invalidate
- write-invalidate cache coherence protocol
- write lock
- write lockout
- write-once protocol
- write penalty
- write protect