Beginner
Complete a first guided exercise with immediate validation.
Beginner · 15 min · SELECTStart →Interactive SQL exercises
Practise SQL online through progressive business cases. Each exercise provides fictional data, hints, result validation and an explained solution.
Start without browsing the whole catalogue
Complete a first guided exercise with immediate validation.
Beginner · 15 min · SELECTStart →Practise with metrics, customers and sales.
SQL · KPI · analyse métierExplore the path →Train with timed, explained question sets.
30 défis · 3 niveauxStart →Show only the name and price of each product.
Level : BeginnerOpen exerciseFind orders over €50, from highest to lowest.
Level : BeginnerOpen exerciseAssociate each order with the name of the customer who placed it.
Level : IntermediateCompare plansDisplay the first three unique categories in alphabetical order.
Level : BeginnerCreate a free accountDisplay clear labeling when a customer’s phone is absent.
Level : BeginnerCreate a free accountCalculate the volume, total and average over a specific area.
Level : BeginnerCompare plansCalculate totals by category and keep only the most important ones.
Level : BeginnerCompare plansCount the orders of each customer without excluding new registrants.
Level : BeginnerCompare plansCalculate the total per customer, then transform this result into a business segment.
Level : IntermediateCompare plansSelect an inclusive interval and check its limits.
Level : BeginnerCreate a free accountReplace multiple OR with a readable business list.
Level : BeginnerCreate a free accountUse a simple text pattern without confusing prefix and content.
Level : BeginnerCreate a free accountDistinguish a missing date from an empty string or status.
Level : BeginnerCreate a free accountTransform a source price with a precise formula and alias.
Level : BeginnerCreate a free accountCreate a readable label from two columns.
Level : BeginnerCreate a free accountCreate a clean dimension before counting customers.
Level : BeginnerCreate a free accountDerive a calendar component without transforming the scope.
Level : BeginnerCompare plansGroup together several channels over the same monthly period.
Level : IntermediateCompare plansFilter a complete period with an exclusive upper bound.
Level : IntermediateCompare plansKeep the starting population and isolate the absence of activity.
Level : IntermediateCompare plansFilter a population without duplicating it by its history.
Level : IntermediateCompare plansOnly aggregate orders that are actually paid.
Level : IntermediateCompare plansUse an aggregated value as a dynamic threshold.
Level : IntermediateCompare plansCreate a single list from two compatible sources.
Level : IntermediateCompare plansCommit 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 plansCommit 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 plansCentralize 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 plansCentralize 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 plansCentralize 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 plansCentralize 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 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 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 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 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 plansEncapsulate 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 plansEncapsulate 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 plansEncapsulate 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 plansEncapsulate 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 plansRetain 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 plansRetain 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 plansRetain 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 plansRetain 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 plansApply 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 plansApply 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 plansApply 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 plansApply 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.