Essential
Looking to sharpen your Data Engineering edge? This track cuts through the noise to focus on the core skills that actually matter through advanced SQL optimization, Spark, and Snowflake patterns used to move and transform data. Whether you're refreshing your knowledge or prepping for high-level interviews, these challenges bridge the gap between basic data movement and production-grade engineering.
What You'll Master
189 questions strategically distributed across 5 essential Data Engineering domains:
SQL 33 questions
Git 15 questions
Spark 20 questions
Snowflake 22 questions
Python 24 questions
Pass Interviews At
Questions sourced from real interviews at top companies:
Google
Amazon
Microsoft
Meta
Netflix
Stripe
Uber
Airbnb
Accenture
Visa
IBM
Adobe
Tesla+ 90 more
Questions in This Track
189 questions you'll work through:
1 Debug SSH Lockout Linux 2 Recursive Keyword Finder Linux 3 Docker Multi-Architecture Image Docker 4 Average Order Value SQLAggregation 5 Join Employees and Departments SQLJoins 6 Filter Orders by Date Range SQLBasic 7 Find Customers Without Orders SQLJoins 8 Use COALESCE for Null Handling SQLData Manipulation 9 Merge Multiple Address Fields SQLData Manipulation 10 String Concatenation in SELECT SQLData Manipulation 11 Find Nth Highest Revenue SQLAggregation 12 Self-Join to Identify Missing Supervisors SQLJoins 13 Year-over-Year Revenue Growth SQLAggregation 14 Above Average Price Products SQLAdvanced 15 Calculate Cumulative Sales SQLAggregation 16 Find Overlapping Date Ranges SQLJoins 17 Set Operation: INTERSECT SQLJoins 18 Subquery for Best Order per Customer SQLJoins 19 Ranking with Dense_Rank SQLAggregation 20 Median Salary by Job Title SQLAggregation 21 String Splitting and Aggregation SQLAggregation 22 Salary Comparison with CTE Aggregation SQLAggregation 23 String Pattern Extraction in Descriptions SQLData Manipulation 24 Nested Subquery for Latest Record SQLJoins 25 Window Function for Moving Average SQLAggregation 26 Re-enrollment Rate Calculator SQLJoins 27 String Pattern Matching Using LIKE SQLJoins 28 Merge Employee and Department Records SQLAdvanced 29 Sequence Products by Price SQLAdvanced 30 Top Categories by Average Price SQLAggregation 31 Customer Order Aggregation SQLJoins 32 Filter Popular Videos on a Streaming Platform SnowflakeFiltering 33 Replace Keywords in Social Media Post Text SnowflakeString Replacement 34 Filter Movies with Missing Box Office Data SnowflakeNull Handling 35 Daily Category Sales SnowflakeJoins 36 Filter and Uppercase Artifacts SnowflakeString Transformation 37 Combine Customer Orders and Products SnowflakeJoins 38 Anonymize User PII Data for a Social Media Platform SnowflakeString Functions 39 Product Sales and Inventory Data SnowflakeAggregation 40 Products and Duplicates SnowflakeDeduplication 41 Mortgage Rate Calculator SnowflakeJoins 42 Weekend Order Detection SnowflakeDatetime Operations 43 Flooring Company Data SnowflakeJoins 44 Rank Top Products by Revenue per Category SnowflakeWindows Functions 45 Highest SEO Score Pages per Domain SnowflakeWindows Functions 46 Math Expressions SnowflakeRegular Expressions 47 CSV and Partitions SparkDataFrame 48 Repartition SparkDataFrame 49 Broadcast Join SparkDataFrame 50 Correcting Social Media Posts SparkDataFrame 51 Daily Category Sales Aggregation SparkAggregate Functions 52 Cache and Performance SparkDataFrame 53 Filter Popular Videos SparkDataFrame 54 Anonymize User PII SparkDataFrame 55 Call Center Daily Stats SparkDataFrame 56 Venture Capital Sector Analysis SparkJoins 57 Window Functions without Partitions SparkWindows Functions 58 Calculating PE Portfolio Values SparkAggregate Functions 59 Mountain Climber Logs SparkWindow Functions 60 Global & Domain SEO Leaders SparkAggregation 61 Tracking Customer Purchase History SparkWindow Functions 62 Contains Duplicate ProgrammingArrays 63 Valid Anagram ProgrammingHash Tables 64 Two Sum ProgrammingArrays 65 Valid Palindrome ProgrammingTwo Pointers 66 Valid Parentheses ProgrammingStacks 67 Binary Search ProgrammingArrays 68 Merge Two Sorted Lists ProgrammingLinked Lists 69 Invert Binary Tree ProgrammingTrees 70 Maximum Depth of Binary Tree ProgrammingTrees 71 Diameter of Binary Tree ProgrammingTrees 72 Balanced Binary Tree ProgrammingTrees 73 Same Tree ProgrammingTrees 74 Subtree of Another Tree ProgrammingTrees 75 Group Anagrams ProgrammingArrays 76 Top K Frequent Elements ProgrammingArrays 77 Product of Array Except Self ProgrammingArrays 78 Longest Consecutive Sequence ProgrammingArrays 79 Two Sum II - Input Array Is Sorted ProgrammingArrays 80 Three Sum ProgrammingArrays 81 Container With Most Water ProgrammingArrays 82 Longest Substring Without Repeating Characters ProgrammingHash Tables 83 Longest Repeating Character Replacement ProgrammingHash Tables 84 Permutation in String ProgrammingHash Tables 85 Daily Temperatures ProgrammingArrays 86 Car Fleet ProgrammingArrays 87 Search a 2D Matrix ProgrammingArrays 88 Koko Eating Bananas ProgrammingArrays 89 Find Minimum in Rotated Sorted Array ProgrammingDSA 90 Search in Rotated Sorted Array ProgrammingArrays 91 Remove Nth Node From End of List ProgrammingLinked Lists 92 Add Two Numbers ProgrammingLinked Lists 93 Lowest Common Ancestor of a BST ProgrammingTrees 94 Binary Tree Level Order Traversal ProgrammingTrees 95 Validate Binary Search Tree ProgrammingTrees 96 Kth Smallest Element in a BST ProgrammingTrees 97 K Closest Points to Origin ProgrammingArrays 98 Kth Largest Element in an Array ProgrammingArrays 99 Task Scheduler ProgrammingArrays 100 Combination Sum ProgrammingArrays 101 Permutations ProgrammingArrays 102 Number of Islands ProgrammingArrays 103 Course Schedule II ProgrammingDFS 104 Graph Valid Tree ProgrammingDFS 105 Network Delay Time ProgrammingDFS 106 Jump Game ProgrammingArrays 107 Jump Game II ProgrammingArrays 108 Gas Station ProgrammingArrays 109 Partition Labels ProgrammingStrings 110 Create Branch from Detached HEAD State Git 111 Rebase Feature Branch Git 112 Apply Specific Stash from Multiple Stashes Git 113 Remove Last Commit and Discard Changes Git 114 Checkout Single File from Another Branch Git 115 Cherry-Pick Specific Commit Git 116 Restore File to Previous Version Git 117 Create an Annotated Tag Git 118 Add Git Submodule Git 119 Update Submodule to Latest Commit Git 120 Stash Work, Fix Bug, Restore and Update Git 121 Remove File from Entire Git History Git 122 Merge Repositories Preserving Both Histories Git 123 Fix Repository with Unrelated Histories Git 124 Recover Lost Commits from Detached HEAD Git 125 Merge Customer Records from Two Sources SnowflakeCombining Data 126 Filter Funded Startups SnowflakeAggregation 127 Assign Row Numbers to Authors per Paper SnowflakeWindows Functions 128 Amusement Park Rating Anomalies SnowflakeAggregate Functions 129 Usage and Accuracy per Model Type SnowflakeAggregation 130 Find the Last Climber per Mountain SnowflakeWindows Functions 131 Track Product Purchases SnowflakeWindows Functions 132 Most Common Order Status SparkDataFrame 133 Calculating Overtime Pay SparkJoins 134 Top Products by Revenue SparkDataFrame 135 Product Summary SparkNull Handling 136 Parsing Comma-Separated Values SparkString Manipulation 137 Number of Connected Components in an Undirected Graph ProgrammingDFS 138 Course Schedule ProgrammingDFS 139 Walls and Gates ProgrammingArrays 140 Surrounded Regions ProgrammingArrays 141 Pacific Atlantic Water Flow ProgrammingArrays 142 Max Area of Island ProgrammingArrays 143 Clone Graph ProgrammingDFS 144 Subsets ProgrammingArrays 145 Binary Tree Right Side View ProgrammingTrees 146 Linked List Cycle ProgrammingLinked Lists 147 Copy List with Random Pointer ProgrammingLinked Lists 148 Reorder List ProgrammingLinked Lists 149 Reverse Linked List ProgrammingLinked Lists 150 Evaluate Reverse Polish Notation ProgrammingStacks 151 Min Stack ProgrammingStacks 152 LRU Cache ProgrammingHash Table 153 Implement Trie (Prefix Tree) ProgrammingHash Table 154 Design Add and Search Words Data Structure ProgrammingString 155 Design Twitter ProgrammingHash Table 156 Sliding Window Median ProgrammingArrays 157 Subarray Sum Equals K ProgrammingArrays 158 Accounts Merge ProgrammingDFS 159 Continuous Subarray Sum ProgrammingArrays 160 Moving Average from Data Stream ProgrammingQueues 161 Top K Frequent Elements in Stream ProgrammingHash Tables 162 Log Aggregator ProgrammingHash Tables 163 Event Stream Deduplicator ProgrammingHash Tables 164 Skew-Aware Key Partitioner ProgrammingHash Tables 165 Hash Join Simulator ProgrammingHash Tables 166 CSV Row Filter and Count ProgrammingPython 167 Analyze Sales Dataset Dimensions and Calculate Total Revenue ProgrammingPython 168 Sort Avro Employee Records by Salary ProgrammingPython 169 Count User Events from JSON Activity Logs ProgrammingPython 170 Split Delimited Column into Separate Columns with Pandas ProgrammingPython 171 Compare SQLite Database and CSV File Records ProgrammingPython 172 Analyze DataFrame Memory Usage ProgrammingPython 173 Time-Series Rolling Window Analysis for Multi-Stock Price Data ProgrammingPython 174 Calculate Descriptive Statistics for Numeric Columns in Pandas ProgrammingPython 175 Decompose Time-Series Data into Trend, Seasonal, and Residual Components ProgrammingPython 176 Parse JSON Log Files and Extract Fields to CSV ProgrammingPython 177 Extract Schema Information from Parquet File Using PyArrow ProgrammingPython 178 Select Specific Columns from Parquet File ProgrammingPython 179 Flatten Nested Struct Columns in Parquet and Export to CSV ProgrammingPython 180 Merge Customer and Purchase Data Using Pandas ProgrammingPython 181 SQL JOIN with Pandas Data Processing and CSV Export ProgrammingPython 182 Insert New Records into SQLite Database from CSV ProgrammingPython 183 Aggregate SQL Query Results with Pandas and Export to Excel ProgrammingPython 184 Aggregate Time-Series Data into Fixed Time Windows ProgrammingPython 185 Export SQLite Database to Parquet Format with Metadata ProgrammingPython 186 Interpolate Missing Values in Irregular Time-Series Sensor Data ProgrammingPython 187 Remove Seasonal Effects from Time-Series Sales Data ProgrammingPython 188 Convert Excel Files with Multiple Sheets to Individual CSV Files ProgrammingPython 189 Combine Data from Multiple Sources into Unified Report ProgrammingPython