❓

Question of the Week

Select All Employees

Easy 10

Return every row from the employees table.

Solve

Questions

QuestionDone
Select All Employees
EasySELECT
Count Total Orders
EasyCOUNT
Find Sales Department Staff
EasyWHERE
Most Expensive Product
EasyORDER BY
Distinct Job Titles
EasyDISTINCT
Orders Placed in 2023
EasyDate Filter
Total Revenue
EasySUM
Customers A–Z
EasyORDER BY
Products Under $50
EasyWHERE
Active vs Inactive Users
EasyGROUP BY
Direct Reports Per Manager
MediumGROUP BY + HAVING
Top 5 Customers by Spend
MediumJOINs
Employees with No Orders
MediumLEFT JOIN
Duplicate Email Addresses
MediumHAVING
Monthly Sales Totals
MediumDate Grouping
Employee Salary Rank by Dept
MediumWindow Functions
Customers Who Ordered 3+ Times
MediumHAVING
Running Total of Daily Sales
MediumWindow Functions
Average Order Value by Region
MediumJOINs + AVG
Products Never Ordered
MediumSubquery
Rolling 7-Day Revenue Average
HardWindow Functions
Month-over-Month Growth %
HardLAG()
Consecutive Login Streak
HardGaps & Islands
Revenue Retention by Cohort
HardCohort Analysis
Median Salary by Department
HardPercentile
Employee Manager Hierarchy
HardRecursive CTE
First Order Per Customer
HardROW_NUMBER() CTE
Sales vs Previous Quarter
HardLAG() + CASE
Customers Active Every Month
HardHAVING + COUNT
Pivot Monthly Sales to Columns
HardCASE Pivot
Filter DataFrame by Column
EasyFiltering
Group By and Sum
Easygroupby()
Handle Missing Values
Easyfillna / dropna
Sort by Multiple Columns
Easysort_values()
Rename Columns
Easydf.rename()
Merge Two DataFrames
Mediumpd.merge()
Apply Custom Function
Mediumdf.apply()
Rolling Window Average
Mediumrolling().mean()
Pivot Table
Mediumpd.pivot_table()
String Operations on Column
Mediumstr accessor

40 questions shown