Important Aggregate SQL Functions for interview

 Aggregate SQL Functions

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1. COUNT: Counts the number of rows in a result set.

2. SUM: Calculates the sum of values in a numeric column.

3. AVG: Calculates the average value of a numeric column.

4.MIN: Finds the minimum value in a column.

5. MAX: Finds the maximum value in a column.

6. FIRST: Returns the first value in a set.

7.LAST: Returns the last value in a set.

8. LEAD: Returns the value of a column for a subsequent row within the result set.

9. LAG: Returns the value of a column for a preceding row within the result set.

10. STDEV: Calculates the standard deviation of a set of values.

11. VAR: Calculates the variance of a set of values.

12. CUME DIST: Calculates the cumulative distribution of a value within a set of values.

13. CORR: Calculates the correlation coefficient between two sets of values.

14. RANK: Assigns a rank to each row based on the values in one or more columns.

15. PERCENT_RANK: Calculates the relative rank of a value within a set.

16. COVAR_POP: Calculates the population covariance between two columns.

17. COVAR_SAMP: Calculates the sample covariance between two columns.

18.GROUP_CONCAT: Concatenates values from multiple rows into a single string.

19. PERCENTILE_CONT: Calculates the value at a specified percentile.

20. PERCENTILE_DISC: Calculates the discrete percentile value.