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if i am not clear on question, please let me knw.. i am just getting to knw db's
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if i am not clear on question, please let me knw.. i am just getting to knw db's

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PS. There is no additional overhead for the PK, just benefit. &nbsp;
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PS. There is no additional overhead for the PK, just benefit.  

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I have 2 tables and i want to retrieve data from them and combine data to do some processing<br />
I haven't made any column as PRIMARY yet .. <br />
<br />
what is better to way do, shud i make col. as PRIMARY KEY in the tables separately or can i also make UNIQUE INDEX .. is unique index similar to making primary key .. <br />
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I have 2 tables and i want to retrieve data from them and combine data to do some processing
I haven't made any column as PRIMARY yet .. 

what is better to way do, shud i make col. as PRIMARY KEY in the tables separately or can i also make UNIQUE INDEX .. is unique index similar to making primary key .. 






primary key vs unique index

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