56 lines (50 loc) · 4.1 KB

SQL Functions with Interview Question Links

Window Functions

Function	Question Links
`ROW_NUMBER()`	3832-Find-users-with-persistent-user-patterns.md, 22__most_expensive_order_per_user_ranked_overall.md, 03_find_users_who_made_their_second_purchase_within_30_days_of_their_first.md, 01_row_number_vs_rank_vs_dense_rank.md, 00_SQL_Scripts_Window_Function_Part1.md
`RANK()`	184-Department-Highest-Salary.md, 31_Most Recent Three Orders.md, 23_highest_grossing_product_per_country_top_2.md, 26_Find the most experienced employee for each project.md, Readme.md
`DENSE_RANK()`	1875-Group-Employees-with-Same-Salary_.md, 185-Department-Top-3-Salaries.md, 178-Rank-Scores.md, 04_users_with_second_purchase.md, 04_Amazon_SQL_DA_Questions.md
`NTILE()`	SQL_Functions_Reference.md
`PERCENT_RANK()`	SQL_Functions_Reference.md
`CUME_DIST()`
`NTH_VALUE()`

Advanced Window Functions

Function	Question Links
`FIRST_VALUE()`
`LAST_VALUE()`
`LAG()`
`LEAD()`
`SUM() OVER()`
`AVG() OVER()`
`COUNT(*) OVER()`

Date & Time Functions

Function	Question Links
`EXTRACT()`
`DATE_FORMAT()`
`CURRENT_DATE()`
`DATEDIFF()`
`DATE + INTERVAL 7 DAY`
`RANGE BETWEEN` (rolling windows)
`DATE_TRUNC()`
`Past N Days` (e.g., CURRENT_DATE - INTERVAL 7 DAY)

Subquery Patterns

Pattern	Question Links
(none listed)

Join Patterns

Pattern	Question Links
`Anti-Join`
`Derived Table`
`Scalar Lookup`
`Self-Join`
`Cross-Join`
`Left Join Filtering Gotcha`

Casting Functions

Function	Question Links
`CAST(date)`
`CAST(varchar)`