15 SQL Commands Every Data Analyst Must Learn
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If you want to work with data professionally, SQL is non-negotiable.
Dashboards, BI tools, AI models, and reports all depend on structured data, and SQL is the language that lets you ask the right questions from that data.
As a data analyst, you don’t need all of SQL — but you must master the essentials.
Below are 15 SQL commands that cover 90% of real-world analyst work.
1. SELECT — Fetching Data
The foundation of SQL. Every analysis starts here.
SELECT * FROM sales;Used to retrieve columns and rows from a table.
2. WHERE — Filtering Records
Filters data based on conditions.
SELECT *
FROM sales
WHERE region = 'North';Critical for isolating relevant data.
3. DISTINCT — Removing Duplicates
Helps identify unique values.
SELECT DISTINCT country
FROM customers;Very common in profiling data.
4. ORDER BY — Sorting Results
Sorts data in ascending or descending order.
SELECT *
FROM sales
ORDER BY sales_amount DESC;Useful for ranking analysis.
5. LIMIT / TOP — Controlling Output Size
Limits the number of rows returned.
SELECT *
FROM sales
ORDER BY sales_amount DESC
LIMIT 10;Perfect for “Top 10” style insights.
6. COUNT() — Counting Rows
Returns the number of records.
SELECT COUNT(*) FROM orders;Used in almost every KPI calculation.
7. SUM() — Adding Values
Aggregates numeric columns.
SELECT SUM(revenue)
FROM sales;Essential for financial metrics.
8. AVG() — Calculating Averages
Finds mean values.
SELECT AVG(order_value)
FROM orders;Used in performance and trend analysis.
9. MIN() & MAX() — Finding Extremes
Identifies smallest and largest values.
SELECT MIN(sales_date), MAX(sales_date)
FROM sales;Helpful for date range checks.
10. GROUP BY — Aggregation by Category
Groups rows for summary analysis.
SELECT region, SUM(revenue)
FROM sales
GROUP BY region;The backbone of analytical queries.
11. HAVING — Filtering Aggregated Data
Filters results after aggregation.
SELECT region, SUM(revenue)
FROM sales
GROUP BY region
HAVING SUM(revenue) > 100000;A common interview favorite.
12. INNER JOIN — Combining Related Tables
Returns matching records from both tables.
SELECT *
FROM orders o
INNER JOIN customers c
ON o.customer_id = c.customer_id;Used constantly in real datasets.
13. LEFT JOIN — Keeping All Primary Data
Keeps all records from the left table.
SELECT *
FROM customers c
LEFT JOIN orders o
ON c.customer_id = o.customer_id;Perfect for detecting missing data.
14. CASE — Conditional Logic
Adds logic similar to IF-ELSE.
SELECT
sales_amount,
CASE
WHEN sales_amount > 50000 THEN 'High'
ELSE 'Low'
END AS sales_category
FROM sales;Extremely valuable for business rules.
15. NULL Handling (IS NULL / COALESCE)
Deals with missing values.
SELECT COALESCE(discount, 0)
FROM sales;Avoids incorrect calculations and blanks.
Why These 15 Commands Matter
With just these commands, you can:
- Analyze trends
- Prepare data for Power BI or Tableau
- Validate dashboards
- Support AI and ML workflows
- Answer 90% of stakeholder questions
You don’t need to be a SQL expert — you need to be SQL effective.
Tools will change.
Dashboards will evolve.
AI will accelerate analysis.But SQL remains the backbone of data work.
If you’re serious about being a data analyst, master these 15 commands — and everything else becomes easier.


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