Category · 8 articles

SQL & Data Interviews

Window functions, CTEs, and the queries that actually get asked.

SQL drills, query optimization, and data-engineering interview prep. Covers analytics roles, data engineer loops, and the LeetCode/HackerRank SQL tracks.

  • leetcode sql
  • hackerrank sql
  • sql interview questions
  • data engineer leetcode
  • leetcode for data engineers
  • leetcode pandas
  • sql window functions
18 min read3,671 words

Data Engineer Interview Loops: SQL, Pipelines, and Tradeoff Stories

LeetCode SQL is one slice — pipelines and operational thinking complete the picture.

  • data engineer leetcode
  • leetcode for data engineers
  • sql interview data engineer
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18 min read3,639 words

CTEs in Interviews: Readability, Recursion, and Performance Intuition

Interviewers reward clarity — nested soup hides bugs you cannot afford.

  • sql cte
  • recursive sql
  • leetcode sql
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18 min read3,604 words

Analytics SQL: CASE, Bucketing, and Funnel Semantics Under Pressure

Funnel questions hide timezone and identity traps — name them early.

  • analytics sql interview
  • sql case when interview
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18 min read3,677 words

SQL Window Functions: Frames, PARTITION BY, and the 80% Patterns

Rank, running totals, and prior-row lookups — with the clarifying questions that prevent silent wrong answers.

  • leetcode sql
  • sql window functions
  • sql interview questions
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19 min read3,705 words

SQL Optimization Interviews: Indexes, Selectivity, and Honest Tradeoffs

You do not need to be a DBA — you need coherent stories about scans and sorts.

  • sql optimization interview
  • index interview sql
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18 min read3,650 words

NULL Semantics in SQL Interviews: Tri-valued Logic and Interview Landmines

COUNT(*) vs COUNT(col) is not trivia — it is a signal you shipped queries.

  • sql null handling
  • sql interview questions
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18 min read3,617 words

SQL Joins and Cardinality: Inner, Outer, and the Duplicate Explosion

Every join multiplies rows — say it before your aggregates lie.

  • sql joins interview
  • hackerrank sql
  • sql interview
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9 min read1,675 words

SQL Interview Questions: The 9 Window Function Patterns That Solve 80% of LeetCode SQL

If you can write a clean window function under pressure, you can pass almost every analytics and data-engineer SQL screen.

  • leetcode sql
  • hackerrank sql
  • sql interview questions
  • sql window functions
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