SQL (Structured Query Language) is a core tool used by data analysts to work with structured data stored in relational databases. It enables efficient data retrieval, filtering, aggregation and transformation to generate meaningful insights for business decision-making.
- Writing SQL queries to extract and analyze data.
- Using aggregation, joins and analytical functions.
- Applying SQL for reporting and business insights.
1. Getting Started with SQL
Understanding SQL fundamentals, data types and database commands establishes the foundation for querying and analyzing data.
2. SQL Queries & Filtering
SQL queries help analysts retrieve relevant records from large datasets by selecting columns, applying conditions and sorting results. Filtering and limiting data makes analysis more focused and efficient.
- SELECT Statement
- Distinct Clause
- WHERE Clause
- Comparison Operators
- Logical Operators
- BETWEEN & IN Operators
- Wildcards Operators
- IS NULL operator
- ORDER BY
- LIMIT Clause
- Aliases
3. Aggregate Functions & Grouping Data
Aggregate functions summarize data into meaningful metrics, such as total sales, average revenue and customer counts. GROUP BY and HAVING help analyze these metrics across categories and filter groups based on specific conditions.
4. Joining Tables & Set Operations
Joins combine related data from multiple tables, enabling analysis across customers, orders, products and other connected datasets. Set operators combine query results to compare or consolidate data from different sources.
5. Data Cleaning & Transformation
Data quality directly affects the accuracy of analytical results. SQL helps identify duplicate records, handle missing values, standardize text, convert data types and transform dates and values into consistent formats.
- NULL Functions
- Finding Duplicate
- Data Type Conversion
- Date & Time Functions
- String Functions
- CASE Statement
6. Advanced Analytical Queries
Subqueries and Common Table Expressions (CTEs) help organize complex analytical logic into manageable steps. Window functions enable row-level analysis, including rankings, running totals and comparisons across related records.
7. Reporting & Query Optimization
SQL transforms raw data into report-ready datasets for business metrics, periodic reports and dashboards. Efficient queries, indexes and execution plans help improve performance when working with large datasets.
8. Exercises, Projects & Interview Questions
Practical exercises and projects help apply SQL concepts to real-world analytical problems, from filtering and aggregation to joins and advanced queries. Interview questions reinforce problem-solving skills and prepare learners for data analyst roles.