Hello sir , i have a doubt regarding index, for ex we have a query. Select *from emp where emp_grade ='A' and class_section ='B'; And we have created index on emp_grade , will index get called if there are more than one where condition?
You can also manipulate a unique data for a colomn with a unique-function based index. CREATE TABLE my_table ( data_col VARCHAR2(100) NOT NULL, deleted VARCHAR2(1) DEFAULT 'N' NOT NULL ); ALTER TABLE my_table ADD( CHECK (deleted IN ('N', 'Y') ENABLE VALIDATE); CREATE UNIQUE INDEX TEST_UK ON my_table (CASE "DELETED" WHEN 'N' THEN "data_col" END); The values in the data_col have to been unique if the deleted-column is "N" if the column is "Y" then the index doesn't see the value for the uniqueness.
Below are some questions asked in an interview and need clarification. 1) Func and a Procedure with same in a package goes under overloading? 2) What all grants required to execute procedure with name schema.PROC1 having DML on schema1.tab1 from schema2.?
@@@SivaAcademy Can you confirm suppose we opened and started working on cursor and in between some records were deleted by another user from the table then still are we able to see the selected all rows of that cursor ?
Hi Sir, I am learning a lot from your videos and they are very very helpful. Could you please explain y index will be used though we use sum function in the select and not used when Upper function is used?
Yes praveen, we can use the user defined function to create the function based index as far as the function is DETERMINISTIC function. Will explain about DETERMINISTIC function in upcoming video please stay tuned.
@Praveen, These index related videos focus the concept of index, and its usage in general from performance tuning aspect. I will be starting videos specific to performance tuning videos., there i will cover in detail related to tuning aspect. Please stay tune. Thanks,Siva
