Difference between primary key and unique key ?
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Answer Posted / ibrahim
PRIMARY KEY is identity of each row. UNIQUE KEY also
identity of each row.
PRIMARY KEY not accepts null values but unique can accept null.
but the core different between primary key and unique is we use primary key to link tow tables with each other but we can not use unique key to do this.
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HI Friends Myself Manoj,i am from bengaluru.i have 1 yr of exp in PLSQL but not upto the mark..now attending interviews but m not able to clear even 1 round..i have attended 3 interviews till today.purpose of writing this query is,i want to know the intreview topics that interviewer going to ask frequently,mainly SCENARIO based questions.IF anybody have any PLSQL projects please give it to me,it will helps me alot.Thanks for your patience.
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