Data Analytics
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Dive into the world of Data Analytics – uncover insights, explore trends, and master data-driven decision making.

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20 most common SQL Interview Questions.

#SQL #Interview

Don’t skip no. 15🔥📷

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📖 Keys In #SQL With Tables Well Explained

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📖  SQL CheatSheet Full Course


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#𝗦𝗤𝗟 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 𝗖𝗵𝗲𝗮𝘁𝘀𝗵𝗲𝗲𝘁 → 𝗖𝗿𝗮𝗰𝗸 𝗔𝗻𝘆 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 𝗪𝗶𝘁𝗵 𝗧𝗵𝗲𝘀𝗲 𝗖𝗼𝗻𝗰𝗲𝗽𝘁𝘀

➜ 𝟭. 𝗦𝗤𝗟 𝗝𝗼𝗶𝗻𝘀 → Combine data from multiple tables
🡆 INNER JOIN → Returns matching records from both tables
🡆 LEFT JOIN → Returns all records from the left table + matches from the right
🡆 RIGHT JOIN → Returns all records from the right table + matches from the left
🡆 FULL JOIN → Returns all records from both tables

➜ 𝟮. 𝗗𝗔𝗧𝗔 𝗙𝗜𝗟𝗧𝗘𝗥𝗜𝗡𝗚 → Retrieve specific records efficiently
🡆 WHERE → Filters rows before aggregation
🡆 HAVING → Filters after aggregation
🡆 BETWEEN, IN, LIKE → Advanced filtering

➜ 𝟯. 𝗔𝗚𝗚𝗥𝗘𝗚𝗔𝗧𝗜𝗢𝗡 & 𝗚𝗥𝗢𝗨𝗣𝗜𝗡𝗚 → Summarize data
🡆 GROUP BY → Groups data based on a column
🡆 COUNT, SUM, AVG, MIN, MAX → Perform calculations

➜ 𝟰. 𝗦𝗨𝗕𝗤𝗨𝗘𝗥𝗜𝗘𝗦 & 𝗖𝗧𝗘𝘀 → Break complex queries
🡆 Subquery → Nested query inside another query
🡆 Common Table Expressions (CTE) → Temporary named query

➜ 𝟱. 𝗜𝗡𝗗𝗘𝗫𝗜𝗡𝗚 & 𝗢𝗣𝗧𝗜𝗠𝗜𝗭𝗔𝗧𝗜𝗢𝗡 → Speed up queries
🡆 Indexes → Improve search speed
🡆 EXPLAIN PLAN → Analyze query performance

➜ 𝟲. 𝗔𝗗𝗩𝗔𝗡𝗖𝗘𝗗 𝗦𝗤𝗟 𝗧𝗢𝗣𝗜𝗖𝗦
🡆 Window Functions → RANK, ROW_NUMBER, LEAD, LAG
🡆 Stored Procedures & Triggers → Automate tasks
🡆 Normalization & Denormalization → Optimize database design

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SQL Query Optimaztion.pdf
897.9 KB
Your SQL query is running.

And running.

And ruuunnniiiiiiiing....⏱️⏱️⏱️⏱️

Not so great for a tool meant to enable us quicker access to data, right?

Swipe for a few tips on how to optimize your #SQL queries, and not let them become a bottleneck in your reporting process.

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📌 How to Design Structured Database Systems Using SQL [Full Book]

✍️ Daniel García Solla
🏷️ #SQL
📌 A Brief Introduction to SQLite

✍️ Mark Mahoney
🏷️ #SQL
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📌 Learn Databases and SQL from Harvard University

✍️ Beau Carnes
🏷️ #SQL
300 Real Time SQL Interview.pdf
4.5 MB
300 Real Time SQL Interview practical Questions Asked at multiple companies
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Anyone who's preparing for an interview just reading theoretical concept will not help definitely you need to have practical hands on in #sql so create table with some data and try this queries running by your self so can help you to understand the logic of similar kind of queries

If you're preparing for an interview this doc will help a lot in the perpetration If you're experienced also freshers can also get hands on by practicing these queries and get confidence.
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Important SQL concepts to master.pdf
3 MB
Important #SQL concepts to master:
- Joins (inner, left, right, full)
- Group By vs Where vs Having
- Window functions (ROW_NUMBER, RANK, DENSE_RANK)
- CTEs (Common Table Expressions)
- Subqueries and nested queries
- Aggregations and filtering
- Indexing and performance basics
- NULL handling

Interview Tips:
- Focus on writing clean, readable queries
- Explain your logic clearly don’t just jump to
#code
- Always test for edge cases (empty tables, duplicate rows)
- Practice optimization: how would you improve performance?


https://t.iss.one/DataAnalyticsX
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SQL Ultimate Cheat Sheet

Standard #SQL, Queries & Management

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