1.Different Types of Joins 2.What is normal distribution 3.Difference between skewness and kurtosis 4.Draw different skewed diagrams on paper and point out mean,median and mode 5.Explain about Window functions 6.difference between Rank and Dense rank 7.write the number of rows obtained after joining tables using left,right and inner join 8.write a query to obtain second highest salary from every department 9.write a query to obtain managers who are working as employees 10.write a query to use self join

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Interview questions for Machine Learning Scientist position

Different types of joins: inner, left, right, full outer
Normal distribution: bell-shaped curve with mean and standard deviation
Skewness: measure of asymmetry in data, Kurtosis: measure of peakedness in data
Window functions: perform calculations across a set of rows that are related to the current row
Rank vs Dense rank: Rank assigns unique rank to each distinct value, Dense rank assigns same rank to ties
Number of rows obtained after joining tables: inner join - only matching rows, left join - all rows from left table and matching rows from right table, right join - all rows from right table and matching rows from left table
Query to obtain second highest salary from every department: use subquery and rank function
Query to obtain managers who are working as employees: use self join and where clause to filter for managers who are also employees
Query to use self join: join a table to itself to compare rows within the same table