In this SQL course you learn to query relational databases and analyse data on your own. It is aimed at beginners in business departments, finance, sales and IT who currently depend on ready-made reports. You write SELECT queries with filters and sorting, link tables with JOINs and summarise values with aggregate functions. You also learn how tables, keys and relationships are structured, so you can interpret results correctly and spot typical errors such as duplicated rows.
What you’ll take away.
- Write simple and filtered queries with SELECT, WHERE, ORDER BY and LIMIT
- Link tables with INNER JOIN and LEFT JOIN and check the row count of the result
- Aggregate data with COUNT, SUM, AVG, GROUP BY and HAVING
- Read primary and foreign keys and understand a simple relational schema
- Change data with INSERT, UPDATE and DELETE while respecting transactions and backups
Your training in detail
- Who is it for?
- Beginners from business departments, finance, sales, support and IT who want to query database data themselves.
- Prerequisites
- No programming knowledge required. Familiarity with spreadsheets is helpful.
- Format & planning
- Suggested format: 2 days live online or on site. Scope depends on prior knowledge.
Agenda: from understanding to application
Our independently developed agenda proposal. Focus areas, lab environment and scope are agreed before booking.
Relational basics: tables, rows, data types, primary and foreign keys, and reading an entity-relationship diagram.
Querying: SELECT, WHERE with AND, OR and IN, LIKE, NULL handling, ORDER BY, DISTINCT and LIMIT.
Joins: INNER JOIN, LEFT JOIN, aliases, multiple joins and typical error patterns such as unintended row multiplication.
Analysis: aggregate functions, GROUP BY, HAVING, CASE expressions, and date and text functions.
Advanced queries: subqueries, common table expressions with WITH and window functions such as ROW_NUMBER and SUM OVER.
Data maintenance: INSERT, UPDATE, DELETE, transactions with COMMIT and ROLLBACK, indexes as a basic idea and advice on working safely with production data.
Suggested exercise: You analyse a sample database of customers, orders and products and answer questions such as revenue by region and month.
Exams, licences & credentials
There is no vendor-neutral SQL exam that this course specifically prepares for. Database vendors offer their own exams. Attending alone does not award a certification. Fees are only included if confirmed in the offer.
Vendor references & review date
Sources checked on 2026-11-03. These sources describe the technology or external exam requirements. They do not imply a partnership with NextNowa.
Your learning content
These objectives describe the training topic. The specific syllabus, duration, dates, trainer and price are agreed before booking.
Frequently asked questions
How long does it take to learn SQL?
You can cover the basics of SELECT, filters, JOINs and GROUP BY in a few days. Confidence comes from regular practice on real questions. Advanced topics such as window functions or performance take longer and usually follow once you have some project experience.
Which SQL dialect does the course use?
The course teaches standard SQL and points out differences between common systems such as PostgreSQL, MySQL and SQL Server. The exercises can usually be adapted to the database your company uses. Tell us your system when you enquire, so that examples and function names fit.
What is the difference between INNER JOIN and LEFT JOIN?
An INNER JOIN returns only rows that have a match in both tables. A LEFT JOIN keeps all rows from the left table and fills missing values from the right with NULL. This matters when you want to see, for example, customers who have not placed an order.
Does SQL & databases include a certificate?
There is no vendor-neutral SQL exam that this course specifically prepares for. Database vendors offer their own exams. Attending alone does not award a certification. Fees are only included if confirmed in the offer.