表中的2个颜色是否相互依赖以避免数据重复？怎么样 [英] 2 coloumns in table have depend upon each other to avoid data duplication? How

问题描述

我想避免数据重复，假设我有一个表名为Schema_tbl，其中包含2个coloums

Schema_tbl列是：

tblNames | primaryKeysCol

数据：

tblCustomer | cmpid

tblCustomer | brchid

tblCustomer | pkid

- 重复值 -

tblCustomer | cmpid



现在如何制作一个复合键，避免重复键复制键复制键复制键



我尝试过的事情：



只有开发的模式我才能解决复合键会被应用但是如何

I want to avoid duplication of data suppose i have a table name Schema_tbl that holds 2 coloums
Schema_tbl columns are :
tblNames | primaryKeysCol
data:
tblCustomer | cmpid
tblCustomer | brchid
tblCustomer | pkid
--duplicated values --
tblCustomer | cmpid

now how to make a composite key that avoids the duplicated of data in primary key coloumns agains composite key

What I have tried:

NOTHING ONLY DEVELOPED SCHEMA I GOOGLED BUT FOUND SOLUTION THAT COMPOSITE KEYS WILL BE APPLIED BUT HOW TO

推荐答案

尝试 -

Try-

ALTER TABLE Schema_tbl
    ADD CONSTRAINT pk_myConstraint PRIMARY KEY (tblNames,primaryKeysCol)

希望，它有帮助：）

Hope, it helps :)

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