Both keys ensure that a column or a combination of columns in a table or relation is unique. The primary key identifies each record in the table, whereas the unique key, with the exception of NULL values, prevents duplicate entries in a field.
The UNIQUE constraint assures that each column's values are unique. The UNIQUE and PRIMARY KEY constraints both guarantee that a column or collection of columns is unique. A UNIQUE constraint is immediately added to a PRIMARY KEY constraint.
A group of one or more table fields/columns that uniquely identify a record in a database table is known as a unique key. It's similar to a primary key in that it can only accept one null value and cannot have duplicate values.
A group of one or more fields/columns in a table that uniquely identify a record in a database table is known as a unique key. It's similar to a primary key in that it accepts just one null value and cannot have duplicate values.
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Aman Kanaujia
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All good , but provide the data also for the assignment , Without data the interest is less day by day from the course. So, try to solve this problem as asap.
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Snehil
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Everything is good but keyboard sounds more harsh and overlap your voice whereas this course is best.
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FAROOK MOHAMMAD
5
Hello sir, explaination is excellent. I have a request please send the db in excel or SQL file.
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Hari Prakash
4
In SQL Join Function's 2nd video - Teacher's voice dose not match with background content that are plays
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Aakash Mavar
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Hello sir
Mera Abhi graduation hu he Mene Mechanical Engineering BTech ki Hai me Data analysis me Apna career Bana skat ho Kya
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Ashok Kumar Sonkar
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Super Duper Traning
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Harshit Chauhan
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How to download in mac m1?
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Swati Patil
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Excellent
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Avinash Rawat
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I want to assignment answer and data. excellent teach
rawatavinash1995@gmail.com
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Pravin Kashid
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excellent teaching technique...one of the best course content...
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