Because oracle handles nulls in different ways actually. For example- distinct, group by, union will consider null= null hence you will see only one row for null. But In case of unique, case statement it treats nullnull hence each null is considered as unique value and allowed.
The partition key is a set of one or more columns that determines the partition for each row. Oracle automatically directs insert, update, and delete operations to the appropriate partition through the use of the partition key.
You're doing a good job! Keep it up 👏👏👏👏
Really helpful for me. Thanks
Great sir !
Sir, if possible can you make a video on "How the Sql query works internally" and also "Where the table and other objects are stored".. Thank you
Sure, thanks.
Question no:18 RAISE_APPLICATION_ERROR range is between -20,000 and -20,999.
Sorry for the typo.
Thank you for helping us
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Hi,can you tell howmany null value is allowed in a unique key column?
Multiple null values are allowed.
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Okay,but if we r saying unique key will not allow any duplicate value,then how come multiple null is allowed?
Because oracle handles nulls in different ways actually.
For example- distinct, group by, union will consider null= null hence you will see only one row for null.
But
In case of unique, case statement it treats nullnull hence each null is considered as unique value and allowed.
Sir could you please let me know that in a unique key column how many null can possible
It depends upon database... in Oracle - multiple nulls are allowed in unique key.
Maximum no of partititon key means? Pls explain
The partition key is a set of one or more columns that determines the partition for each row. Oracle automatically directs insert, update, and delete operations to the appropriate partition through the use of the partition key.
Please post more and more vedios on SQL and plsql