Meet your database
A database is a collection of related tables. A table is like an Excel sheet: columns describe fields, rows describe records. SQL asks questions about those records. Our sample shop has customers, orders, products, order_items and employees.
हिन्दी में समझें
डेटाबेस आपस में जुड़ी टेबलों का संग्रह है। टेबल Excel शीट जैसी है: कॉलम जानकारी का प्रकार और पंक्ति एक रिकॉर्ड है। SQL से रिकॉर्ड पर सवाल पूछते हैं। यहाँ नमूना दुकान का डेटा है।
अभ्यास: products के सभी कॉलम और पंक्तियाँ दिखाएँ।
Hinglish mein samjhein
Database related tables ka collection hai. Table Excel sheet jaisi: columns fields aur rows records hain. SQL se data par sawaal poochte hain. Yahan sample shop ka data hai.
Practice: products ke saare columns aur rows dikhao.
A small SQL example
SELECT * FROM customers;Examples use the fictional shop database bundled with the SQL playground: customers, products, orders, order_items and employees. The engine is SQLite; other SQL dialects may differ.
Try this example in the SQL playground →Practise this idea
Show all columns and rows from products.
Check answer & explanation
SELECT * FROM products;SELECT * returns every column from the named table. FROM products changes the source from customer records to product records.
Stuck in the course? Choose Check answer for either the challenge or quiz. Read the explanation and continue to the next lesson at your own pace.
Check your understanding
A row usually represents…
Check the quiz answer
One record
A database is a collection of related tables. A table is like an Excel sheet: columns describe fields, rows describe records. SQL asks questions about those records. Our sample shop has customers, orders, products, order_items and employees.
References & corrections
Use the official SQLite documentation for full language rules. Read how these lessons are made and checked. Found a mistake? Report it to Excel Keys with this lesson URL and a reproducible example.