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SQL for Monthly Active Developers
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SQL for Monthly Active Developers

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the monthly active developers from a mock database of smart contract interactions.

Use the developers and contract_interactions tables. Count a developer as active in a month when they have at least one successful interaction during that calendar month.

Output

  1. One row per month with columns month and active_developers
  2. Include only months containing at least one active developer
  3. Order chronologically by month

Schema

developers
ColumnTypeDescription
developer_idPKINTUnique identifier for a developer
wallet_addressVARCHAR(42)Blockchain wallet address associated with the developer
developer_nameVARCHAR(100)Display name of the developer
contract_interactions
ColumnTypeDescription
interaction_idPKINTUnique identifier for an interaction
wallet_addressVARCHAR(42)Wallet address that initiated the interaction
contract_addressVARCHAR(42)Smart contract address involved in the interaction
interacted_atTIMESTAMPTimestamp when the interaction occurred
statusVARCHAR(20)Interaction result status
Tablesdeveloperscontract_interactions
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Your question is SQL for Monthly Active Developers. Start with the requirements and the two tables in the Question tab.

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