不同行-基于两个字段 [英] Distinct Row - Based on two fields

问题描述

有没有一种方法可以使表的重复项基于两个字段?

Is there a way to have a table definition that bases its Non-Duplication on two fields?

通过这个我有3列 gid，cid，价格

By this i have 3 columns gid, cid, price

条件:

• 1个gid只能有1个cid
• 可以有多个cid，只要有多个gid并且不违反标准1

• There can only be 1 cid for 1 gid
• There can be multiple cid's as long as there are multiple gid's and criteria 1 is not violated

如果可能的话，我基本上希望在表设计中有限制.不知道是否有可能我想问.

I basically want to have the restriction in the Table Design, if possible. Not sure if its possible just figured i would ask.

好的澄清一下，我也有两个索引，一个在gid上，另一个在cid上，我可以用两个索引来确定唯一性吗?该表基本上是一个Join表，因为所绘制的两个表之间具有1-Many关系，因为它们的对应关系对其ID是唯一的.

Ok a little clarification, i have two indexes as well, one on gid and other is on cid, can i have the two indexes determine Uniqueness? The table is basically a Join table since the two tables drawn in have a 1-Many relationship, in so far as their counterpart is unique to its id.

表/索引声明:

• gid {Numeric:Long}(主要:否，唯一性:否，忽略空值:否)[FK]
• cid {Numeric:Long}(主要:否，唯一性:否，忽略空值:否)[FK]
• 价格{Numeric:Single}

用法:

cid 1-很多女同志
• cid源自tblCat(作为PK)
• cid 1-Many gid
  • cid is derived from tblCat (as the PK)
  • gid源自tblGrp(作为PK)

  推荐答案

  在MS Access中创建多字段索引没有困难.您只需单击索引按钮(闪电)，然后选择所需的内容即可.

  There is no difficulty in creating multi-field indexes in MS Access. You can simply click the indexes button (lightning flash) and choose what you need.

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