Interactive SQL exercises
Solved SQL exercises: practise from beginner to advanced
Practise SQL online through progressive business cases. Each exercise provides fictional data, hints, result validation and an explained solution.
62 exercises shown
SELECTNo account
Select the correct columns
Show only the name and price of each product.
Level : BeginnerOpen exerciseWHERE · ORDER BYNo account
Filter and sort orders
Find orders over €50, from highest to lowest.
Level : BeginnerOpen exerciseINNER JOINSQL Essentials
Connect customers and orders
Associate each order with the name of the customer who placed it.
Level : IntermediateCompare plansDISTINCT · LIMITDiscovery
List unique categories
Display the first three unique categories in alphabetical order.
Level : BeginnerCreate a free accountNULL · COALESCEDiscovery
Replace a NULL value with COALESCE
Display clear labeling when a customer’s phone is absent.
Level : BeginnerCreate a free accountCOUNT · SUM · AVGSQL Essentials
Calculate paid order indicators
Calculate the volume, total and average over a specific area.
Level : BeginnerCompare plansGROUP BY · HAVINGSQL Essentials
Group revenue by category
Calculate totals by category and keep only the most important ones.
Level : BeginnerCompare plansLEFT JOIN · COUNTSQL Essentials
Keep customers without orders
Count the orders of each customer without excluding new registrants.
Level : BeginnerCompare plansCTE · CASESQL Essentials
Segment customers with a CTE
Calculate the total per customer, then transform this result into a business segment.
Level : IntermediateCompare plansBETWEENDiscovery
Filter a price range
Select an inclusive interval and check its limits.
Level : BeginnerCreate a free accountINDiscovery
Filter multiple statuses
Replace multiple OR with a readable business list.
Level : BeginnerCreate a free accountLIKEDiscovery
Search for a prefix with LIKE
Use a simple text pattern without confusing prefix and content.
Level : BeginnerCreate a free accountIS NULLDiscovery
Identify missing deliveries
Distinguish a missing date from an empty string or status.
Level : BeginnerCreate a free accountExpressions · ROUNDDiscovery
Calculate a price including tax
Transform a source price with a precise formula and alias.
Level : BeginnerCreate a free accountText · ConcatenationDiscovery
Assemble a product label
Create a readable label from two columns.
Level : BeginnerCreate a free accountTRIM · UPPER · DISTINCTDiscovery
Normalize a list of cities
Create a clean dimension before counting customers.
Level : BeginnerCreate a free accountDates · EXTRACTSQL Essentials
Extract the year of registration
Derive a calendar component without transforming the scope.
Level : BeginnerCompare plansDates · GROUP BYSQL Essentials
Calculate monthly revenue
Group together several channels over the same monthly period.
Level : IntermediateCompare plansDates · WHERESQL Essentials
Analyze a quarter with limits
Filter a complete period with an exclusive upper bound.
Level : IntermediateCompare plansLEFT JOIN · HAVINGSQL Essentials
Find customers without orders
Keep the starting population and isolate the absence of activity.
Level : IntermediateCompare plansEXISTSSQL Essentials
Test for the existence of a large order
Filter a population without duplicating it by its history.
Level : IntermediateCompare plansJOIN · AVGSQL Essentials
Calculate the average basket per customer
Only aggregate orders that are actually paid.
Level : IntermediateCompare plansSubquery · AVGSQL Essentials
Compare to average price
Use an aggregated value as a dynamic threshold.
Level : IntermediateCompare plansUNIONSQL Essentials
Merge customers and prospects
Create a single list from two compatible sources.
Level : IntermediateCompare plansTraining scenariosThese contextual repetitions reinforce an existing method. They preserve every historical link without pretending to be new canonical problems.Browse 118 scenarios
118 exercises shown
TRANSACTION · SAVEPOINT · ROLLBACKSQL Pro
Protect an HR change 4 · training scenario
Commit a correct change and undo only the incorrect step. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansTRANSACTION · SAVEPOINT · ROLLBACKSQL Pro
Protect an audit change 5 training scenario
Commit a correct change and undo only the incorrect step. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansCREATE VIEWSQL Pro
Create a reusable billing view 2 training scenario
Centralize a definition of active data without copying the query. You must produce the result, check it on the source data and explain what it allows you to decide in this billing system.
Level : AdvancedCompare plansCREATE VIEWSQL Pro
Create a reusable logistics view 3 training scenario
Centralize a definition of active data without copying the query. You must produce the result, check it on the source data and explain what it allows you to decide in this national expeditions.
Level : AdvancedCompare plansCREATE VIEWSQL Pro
Create a reusable HR 4 view · training scenario
Centralize a definition of active data without copying the query. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansCREATE VIEWSQL Pro
Create a reusable view audit 5 training scenario
Centralize a definition of active data without copying the query. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansCREATE INDEX · EXPLAINSQL Pro
Indexing a billing search 2 · training scenario
Create a targeted index and then verify its presence before interpreting a plan. You must produce the result, check it on the source data and explain what it allows you to decide in this billing system.
Level : AdvancedCompare plansCREATE INDEX · EXPLAINSQL Pro
Indexing a logistics search 3 · training scenario
Create a targeted index and then verify its presence before interpreting a plan. You must produce the result, check it on the source data and explain what it allows you to decide in this national expeditions.
Level : AdvancedCompare plansCREATE INDEX · EXPLAINSQL Pro
Index an HR search 4 · training scenario
Create a targeted index and then verify its presence before interpreting a plan. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansCREATE INDEX · EXPLAINSQL Pro
Indexing a search audit 5 · training scenario
Create a targeted index and then verify its presence before interpreting a plan. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansCREATE FUNCTION · SQLSQL Pro
Create a billing business function 2 training scenario
Encapsulate pure, typed, reusable computation. You must produce the result, check it on the source data and explain what it allows you to decide in this billing system.
Level : AdvancedCompare plansCREATE FUNCTION · SQLSQL Pro
Create a logistics business function 3 · training scenario
Encapsulate pure, typed, reusable computation. You must produce the result, check it on the source data and explain what it allows you to decide in this national expeditions.
Level : AdvancedCompare plansCREATE FUNCTION · SQLSQL Pro
Create an HR business function 4 · training scenario
Encapsulate pure, typed, reusable computation. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansCREATE FUNCTION · SQLSQL Pro
Create an audit business function 5 training scenario
Encapsulate pure, typed, reusable computation. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansTRIGGER · OLD · NEWSQL Pro
Logging an invoicing modification 2 · training scenario
Retain the value before and after a change is actually executed. You must produce the result, check it on the source data and explain what it allows you to decide in this billing system.
Level : AdvancedCompare plansTRIGGER · OLD · NEWSQL Pro
Historicize a logistics modification 3 · training scenario
Retain the value before and after a change is actually executed. You must produce the result, check it on the source data and explain what it allows you to decide in this national expeditions.
Level : AdvancedCompare plansTRIGGER · OLD · NEWSQL Pro
Logging an HR modification 4 · training scenario
Retain the value before and after a change is actually executed. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansTRIGGER · OLD · NEWSQL Pro
Logging an audit modification 5 · training scenario
Retain the value before and after a change is actually executed. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansROLE · GRANT · REVOKESQL Pro
Grant billing read access 2 training scenario
Apply the principle of least privilege to a laboratory table. You must produce the result, check it on the source data and explain what it allows you to decide in this billing system.
Level : AdvancedCompare plansROLE · GRANT · REVOKESQL Pro
Grant Logistics Playback Access 3 · Training Scenario
Apply the principle of least privilege to a laboratory table. You must produce the result, check it on the source data and explain what it allows you to decide in this national expeditions.
Level : AdvancedCompare plansROLE · GRANT · REVOKESQL Pro
Grant read access hr 4 · training scenario
Apply the principle of least privilege to a laboratory table. You must produce the result, control it on the source data and explain what it allows you to decide in this human resources management.
Level : AdvancedCompare plansROLE · GRANT · REVOKESQL Pro
Grant read access to audit 5 training scenario
Apply the principle of least privilege to a laboratory table. You must produce the result, check it on the source data and explain what it allows you to decide in this audit log.
Level : AdvancedCompare plansTwo focused paths reuse these experiences.
Progress remains shared: no content is duplicated.
3 exercises are available without an account, followed by 12 more in the free Discovery space. The catalogue contains a total of 62 canonical experiences. Run a first query.