🚨 90% of SQL learners get this wrong — can you solve it? While exploring SQL problems by Ankit Bansal, I came across a deceptively simple question that really tests your understanding of data patterns, not just syntax. 👉 𝐏𝐫𝐨𝐛𝐥𝐞𝐦 𝐒𝐜𝐞𝐧𝐚𝐫𝐢𝐨: You’re given a table that stores daily task results (success / fail). Your challenge is to: ➡️ Identify continuous streaks of the same state ➡️ Merge them into a single row with start date and end date Sounds easy… until you try it 😄 👉 𝐓𝐚𝐛𝐥𝐞 𝐒𝐞𝐭𝐮𝐩: create table tasks ( date_value date, state varchar(10) ); insert into tasks values ('2019-01-01','success'), ('2019-01-02','success'), ('2019-01-03','success'), ('2019-01-04','fail'), ('2019-01-05','fail'), ('2019-01-06','success'); 👉 𝐄𝐱𝐩𝐞𝐜𝐭𝐞𝐝 𝐎𝐮𝐭𝐩𝐮𝐭: start_date | end_date | state -----------|------------|-------- 2019-01-01 | 2019-01-03 | success 2019-01-04 | 2019-01-05 | fail 2019-01-06 | 2019-01-06 | success 🧠 𝐓𝐡𝐢𝐬 𝐩𝐫𝐨𝐛𝐥𝐞𝐦 𝐢𝐬 𝐚 𝐜𝐥𝐚𝐬𝐬𝐢𝐜 𝐞𝐱𝐚𝐦𝐩𝐥𝐞 𝐨𝐟: Pattern recognition in data Real-world analytics scenarios (streaks, sessions, trends) Thinking beyond basic GROUP BY 💬 Drop your approach in the comments — curious to see different ways to solve this! And if you’ve solved it before, how did you think about it? Shoutout to Ankit Bansal for consistently sharing high-quality SQL problems 🙌 #SQL #DataAnalytics #DataEngineering #InterviewPrep #LearnSQL
SQL Streaks Problem: Identify Continuous Task Results
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Learning SQL in 2025? Start here! SQL is like asking questions to a big box of data You type a query, and it gives you the answer. Here's how you can learn step by step: 1 Basics - Learn how to pick data using SELECT, WHERE, ORDER BY, GROUP BY. 2 Filtering - Search only what you need with conditions like IN, BETWEEN. 3 Joins - Combine data from different tables (INNER, LEFT, RIGHT, FULL). 4 Window Functions - Do smart tricks like ranking, finding next/previous values. 5 Dates - Work with time: today, yesterday, months, years. 6 Advanced Stuff - Play with stats, ML tools, and more. 7 CTEs & Subqueries - Break big problems into small easy queries. 8 Speed Tips - Use indexes, don't SELECT *, write clean queries. ✓ How to practice: - Start with small queries. - Use sample data. - Try joins and date functions. - Solve real-world problems. - Do daily practice. SQL is not hard. It's like learning a new language. The more you practice, the better you get! Save this if you're learning SQL or share it with a friend who is. Note: Reposting for new-audience Gif credit: sai kumar #dataanalyst #sql #datascience #dataengineer
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Learning SQL in 2026? Start here! SQL is like asking questions to a big box of data 📊 You type a query, and it gives you the answer. Here’s how you can learn step by step: 1️⃣ Basics – Learn how to pick data using SELECT, WHERE, ORDER BY, GROUP BY. 2️⃣ Filtering – Search only what you need with conditions like IN, BETWEEN. 3️⃣ Joins – Combine data from different tables (INNER, LEFT, RIGHT, FULL). 4️⃣ Window Functions – Do smart tricks like ranking, finding next/previous values. 5️⃣ Dates – Work with time: today, yesterday, months, years. 6️⃣ Advanced Stuff – Play with stats, ML tools, and more. 7️⃣ CTEs & Subqueries – Break big problems into small easy queries. 8️⃣ Speed Tips – Use indexes, don’t SELECT *, write clean queries. ✅ How to practice: – Start with small queries. – Use sample data. – Try joins and date functions. – Solve real-world problems. – Do daily practice. 👉 SQL is not hard. It’s like learning a new language. The more you practice, the better you get! ♻️ Save this if you’re learning SQL or share it with a friend who is. Note: Reposting for new-audience Gif credit : sai kumar #dataanalyst #sql #datascience #dataengineer
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SQL simplified. 📂✨ Whether it's DQL for data fetching or DML for updates, keeping the fundamentals organized is key. Saving this one for my next technical interview prep! 📝 Which part of SQL do you find the trickiest? For me, it’s nested subqueries! 😅👇 #SQL #Coding #DataAnalytics #TechTips #JavaFullstack
Data Analyst | Turning Data into Business Insights with SQL & Power BI | 2000+ Topmate Sessions | 10M+ Views | 59K+ LinkedIn
Learning SQL in 2026? Start here! SQL is like asking questions to a big box of data 📊 You type a query, and it gives you the answer. Here’s how you can learn step by step: 1️⃣ Basics – Learn how to pick data using SELECT, WHERE, ORDER BY, GROUP BY. 2️⃣ Filtering – Search only what you need with conditions like IN, BETWEEN. 3️⃣ Joins – Combine data from different tables (INNER, LEFT, RIGHT, FULL). 4️⃣ Window Functions – Do smart tricks like ranking, finding next/previous values. 5️⃣ Dates – Work with time: today, yesterday, months, years. 6️⃣ Advanced Stuff – Play with stats, ML tools, and more. 7️⃣ CTEs & Subqueries – Break big problems into small easy queries. 8️⃣ Speed Tips – Use indexes, don’t SELECT *, write clean queries. ✅ How to practice: – Start with small queries. – Use sample data. – Try joins and date functions. – Solve real-world problems. – Do daily practice. 👉 SQL is not hard. It’s like learning a new language. The more you practice, the better you get! ♻️ Save this if you’re learning SQL or share it with a friend who is. Note: Reposting for new-audience Gif credit : sai kumar #dataanalyst #sql #datascience #dataengineer
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Learning SQL in 2025? Start here! SQL is like asking questions to a big box of data 📊 You type a query, and it gives you the answer. Here’s how you can learn step by step: 1️⃣ Basics – Learn how to pick data using SELECT, WHERE, ORDER BY, GROUP BY. 2️⃣ Filtering – Search only what you need with conditions like IN, BETWEEN. 3️⃣ Joins – Combine data from different tables (INNER, LEFT, RIGHT, FULL). 4️⃣ Window Functions – Do smart tricks like ranking, finding next/previous values. 5️⃣ Dates – Work with time: today, yesterday, months, years. 6️⃣ Advanced Stuff – Play with stats, ML tools, and more. 7️⃣ CTEs & Subqueries – Break big problems into small easy queries. 8️⃣ Speed Tips – Use indexes, don’t SELECT *, write clean queries. ✅ How to practice: – Start with small queries. – Use sample data. – Try joins and date functions. – Solve real-world problems. – Do daily practice. 👉 SQL is not hard. It’s like learning a new language. The more you practice, the better you get! ♻️ Save this if you’re learning SQL or share it with a friend who is. Note: Reposting for new-audience #dataanalyst #sql #datascience #dataengineer
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SQL is one of those skills where the basics can take you far—but mastering the right functions is what truly sets you apart. Writing efficient queries isn’t about complexity; it’s about knowing what to use and when. Functions like COALESCE, CASE, and window functions such as ROW_NUMBER and RANK are incredibly powerful and widely used in real-world scenarios. Over time, I’ve realized that strong SQL skills are not about memorizing syntax—they’re about thinking in terms of data transformation: • How do you handle null values? • How do you rank or deduplicate records? • How do you turn raw data into meaningful insights? The more you practice these concepts in real-world situations, the more natural SQL becomes. At the end of the day, SQL isn’t just a query language—it’s the foundation of how we work with data. 📌 Save this post for later 🔁 Repost if you found this helpful 🔔 Follow Gautam Kumar for more insights on Data Science and Analytics Credit: Respective Owner #SQL #DataAnalytics #DataScience #SQLTips #DataEngineering #BusinessIntelligence #Analytics #LearnSQL #DataTransformation #TechCareers
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I wish I had this when I started learning SQL… Instead of solving random queries, These 25 reusable SQL patterns can cover ~80% of real-world problems 🚀 From basics to advanced use cases 👇 ✔️ 𝗙𝗶𝗹𝘁𝗲𝗿𝗶𝗻𝗴 & 𝗮𝗴𝗴𝗿𝗲𝗴𝗮𝘁𝗶𝗼𝗻𝘀 ✔️ 𝗝𝗼𝗶𝗻𝘀 & 𝗮𝗻𝘁𝗶-𝗷𝗼𝗶𝗻𝘀 ✔️ 𝗪𝗶𝗻𝗱𝗼𝘄 𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻𝘀 (𝗧𝗼𝗽-𝗡, 𝗿𝘂𝗻𝗻𝗶𝗻𝗴 𝘁𝗼𝘁𝗮𝗹𝘀, 𝗿𝗮𝗻𝗸𝗶𝗻𝗴) ✔️ 𝗖𝗼𝗵𝗼𝗿𝘁𝘀, 𝗳𝘂𝗻𝗻𝗲𝗹𝘀 & 𝗿𝗲𝘁𝗲𝗻𝘁𝗶𝗼𝗻 ✔️ 𝗗𝗮𝘁𝗮 𝗰𝗹𝗲𝗮𝗻𝗶𝗻𝗴, 𝗱𝗲-𝗱𝘂𝗽𝗹𝗶𝗰𝗮𝘁𝗶𝗼𝗻 & 𝘀𝗲𝘀𝘀𝗶𝗼𝗻𝗶𝘇𝗮𝘁𝗶𝗼𝗻 ✔️ 𝗔𝗱𝘃𝗮𝗻𝗰𝗲𝗱 𝗽𝗮𝘁𝘁𝗲𝗿𝗻𝘀 𝗹𝗶𝗸𝗲 𝗿𝗲𝗰𝘂𝗿𝘀𝗶𝗼𝗻 & 𝗮𝘁𝘁𝗿𝗶𝗯𝘂𝘁𝗶𝗼𝗻 💡 The biggest mistake? Practicing SQL questions randomly without understanding patterns. Once you start recognizing patterns, Every new problem feels familiar. 📌 If you're preparing for interviews or working with data: Don’t memorize queries - understand use-cases. This is the kind of SQL thinking that actually matters in real jobs. 💬 Which SQL pattern do you struggle with the most? 👉 Follow Muhammad Nouman for more practical data engineering & SQL content #SQL #DataEngineering #DataAnalytics #BigData #InterviewPrep #LearnSQL #TechCareers #CareerGrowth
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Learning SQL in 2026? Start here! SQL is like asking questions to a big box of data You type a query, and it gives you the answer. Here's how you can learn step by step: 1 Basics - Learn how to pick data using SELECT, WHERE, ORDER BY, GROUP BY. 2 Filtering - Search only what you need with conditions like IN, BETWEEN. 3 Joins Combine data from different tables (INNER, LEFT, RIGHT, FULL). 4 Window Functions - Do smart tricks like ranking, finding next/previous values. 5 Dates - Work with time: today, yesterday, months, years. 6 Advanced Stuff - Play with stats, ML tools, and more. 7 CTES & Subqueries - Break big problems into small easy queries. 8 Speed Tips - Use indexes, don't SELECT *, write clean queries. How to practice: Start with small queries. Use sample data. Try joins and date functions. Solve real-world problems. Do daily practice. ← SQL is not hard. It's like learning a new language. The more you practice, the better you get! Save this if you're learning SQL or share it with your friends #SQL #Dataanalyst #Dataanalysis
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Most people think SQL is just about writing queries. But the truth is… It’s about 𝘁𝗵𝗶𝗻𝗸𝗶𝗻𝗴 𝗶𝗻 𝗱𝗮𝘁𝗮. When I started learning SQL, I was just memorizing syntax. SELECT this… WHERE that… GROUP BY something. It didn’t work. Everything changed when I understood why each concept exists... not just how to write it. This cheat sheet covers the core building blocks every data analyst actually uses: • Filtering data (WHERE) • Structuring insights (GROUP BY, HAVING) • Combining data (JOINS) • Analyzing patterns (WINDOW FUNCTIONS) • Handling real-world messy data (NULLs, CASE, CTEs) If you master these, you don’t just write queries… You start solving real business problems. Save this post if you’re learning SQL... you’ll come back to it again and again. Which concept do you struggle with the most? #SQL #DataAnalytics #DataAnalyst #LearnSQL #DataScience #Analytics #TechSkills #CareerGrowth
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Day 8 of My SQL Learning Journey | Mastering SQL Functions 🧠💡 Today wasn’t just about writing queries — it was about thinking in functions. A shift from “how to get data” → “how to transform data into insights.” I explored how SQL itself can act like a powerful data-processing engine: 🔹 Single-Row Functions Worked on numeric, string, and date functions to clean, format, and standardize data at a granular level. 🔹 Aggregate Functions Used COUNT, SUM, AVG, MIN, MAX to summarize large datasets and extract meaningful patterns. 🔹 Analytic (Window) Functions This was a game-changer 🚀 Performing calculations across rows without losing row-level detail — super useful for rankings, running totals, and comparisons. 🔹 Conditional Functions CASE, COALESCE, NULLIF helped me introduce logic directly into queries — making SQL smarter and more dynamic. 🔹 Conversion Functions Handled data type transformations like TO_CHAR, TO_DATE, TO_NUMBER for precision and flexibility. 🔹 System & Utility Functions Started understanding how the database “thinks” — context, environment, and metadata. 💡 What really clicked today: 👉 SQL is not just a querying language. 👉 It’s a data transformation tool. 👉 It allows you to analyze, clean, and tell stories — all in one place. The more I learn functions, the more I realize: Less dependency on Excel/Python for basic transformations = More efficiency ⚡ 🧠 Key Takeaway: Good analysts don’t just extract data… They shape it before anyone else even sees it. Consistency > Motivation Clarity > Complexity Day 8 ✅ | Day 9 Loading... 📊🔥 #SQL #DataAnalytics #LearningInPublic #Consistency #AnalyticsMindset #CareerGrowth
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🧠 𝐏𝐨𝐬𝐭𝐠𝐫𝐞𝐒𝐐𝐋 𝐏𝐢𝐭𝐟𝐚𝐥𝐥𝐬 𝐂𝐡𝐞𝐚𝐭 𝐒𝐡𝐞𝐞𝐭 (𝘞𝘩𝘢𝘵 𝘣𝘳𝘦𝘢𝘬𝘴 𝘚𝘘𝘓 𝘲𝘶𝘦𝘳𝘪𝘦𝘴 𝘪𝘯 𝘳𝘦𝘢𝘭 𝘭𝘪𝘧𝘦) After teaching SQL, I’ve noticed something: Most query problems are not about syntax… They’re about logic, data, and assumptions. Here are 10 𝐜𝐨𝐦𝐦𝐨𝐧 𝐏𝐨𝐬𝐭𝐠𝐫𝐞𝐒𝐐𝐋 𝐩𝐢𝐭𝐟𝐚𝐥𝐥𝐬 every analyst should know 👇 1️⃣ JOIN Problems Symptom: Too many rows after joining tables 👉 Cause: Wrong join logic (many-to-many explosion) 2️⃣ Case & Space Issues Symptom: Query returns 0 rows but data exists 👉 Cause: 'Nigeria' ≠ 'nigeria ' 3️⃣ Performance Issues Symptom: Query is fast on small data, slow in production 👉 Cause: Missing indexes 4️⃣ DISTINCT Misuse Symptom: Duplicates still appear 👉 Cause: DISTINCT works on full rows, not one column 5️⃣ NULL Problems Symptom: Calculations (like revenue) look too low 👉 Cause: NULL values break arithmetic 6️⃣ Date Filtering Errors Symptom: Missing records for a specific day 👉 Cause: Timestamp vs date mismatch 7️⃣ GROUP BY Mistakes Symptom: Aggregated results look incorrect 👉 Cause: Wrong grouping level 8️⃣ Aggregation Errors Symptom: “column must appear in GROUP BY” 👉 Cause: Mixing aggregated & non-aggregated fields 9️⃣ Unsafe DELETE Symptom: Important data lost 👉 Cause: No preview before deletion 🔟 Slow Subqueries Symptom: Query takes too long 👉 Cause: Inefficient IN instead of EXISTS or JOIN 🧠 Simple Debug Framework When your SQL looks wrong, check: 1️⃣ JOIN logic 2️⃣ Data quality (NULLs, casing, spaces) 3️⃣ Filters (dates, conditions) 4️⃣ Aggregation logic 5️⃣ Performance (indexes) 💡 One thing I tell my mentees: SQL is not hard because of syntax. It’s hard because small mistakes create big lies. #PostgreSQL #SQL #DataAnalytics #DataEngineering #BusinessIntelligence #Analytics
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