What Is The Difference Between Primary Key & Super Key
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Primary Key is a column which uniquely identifies all records in a table. For example EmployeeID column in an Employee table.
If you add another column to a PK, like (EmployeeID+FirstName) it still identifies identifies all rows uniquely, is known as Super Key.
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Answer / tanmay dutta
Primary Key : Unique No. Not null.No duplicate.exam:Student_Id.
Super Key : Like (student_id + Student Name)
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Answer / anil kumar dubey
A candidate key that uniquely identifies a row in a table is called primary key.
A superkey (composite key) is a combination of columns that uniquely identifies any row within a relational database management system (RDBMS) table.
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can any one say how to update the following senario I have a table <srabank> in which the table structure is as follows ANAME ACCNO LOCATION ACCTYPE BAL SBanuPrakash 31518746291 Punganur deposit 4000 Sreenivas 31518746292 mahoobnagar current 14000 Ranjith 31518746293 Karimnagar Savings 2000 Giresh 31518746294 Chennai deposit 40000 Boo 31518746295 Chennai Savings 20000 Jay 31518746296 Valachari Savings 1000 tirumalraj 31518746297 Vellore Savings 8000 The senario is We need to select one account number and check the balance after checking the balance if the balance exist we need to transfer to another account . in the from account the amount need to be reduced and in the to account the amount needed to be added. for example for the <accountno> <31518746291> the balance is <4000> for the <accno> <31518746292> the balance is <14000> after transferring the balance the details will look as follows <accno><31518746291> <bal> <2000> <accno><31518746292> <bal> <16000> the above mentioned two statment will come under the final result.
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