ClientDB gives your OutSystems apps a real database inside the user's browser, built on IndexedDB. Data survives page reloads and works without a server round trip. It is useful for offline-friendly screens, drafts, caches, user preferences and fast local lookups.

All functionality is exposed as 35 client actions that take and return JSON text. Create tables with a schema, insert and update records, run queries (exact match, lists, ranges, prefix, contains), sort and page results, and group several writes into a single transaction that rolls back on failure.

Every action returns IsSuccess and ErrorMessage, so you can handle errors in your flow without exceptions. Actions wait for the database work to finish before returning, so outputs are ready on the next node.

• Browser database on IndexedDB: data persists across page reloads and sessions
• 35 client actions, no server calls and no entities needed
• Schema-based setup: tables with a key, auto-increment IDs and indexes
• Full CRUD: Insert, InsertBulk, Update, UpdateWhere, Upsert, UpsertBulk, DeleteById, DeleteBulk, DeleteWhere, DeleteRange
• Rich queries: Query, QueryIn, QueryMultiple, QueryRange (numeric or text), QueryStartsWith, case-insensitive Search
• Reading helpers: GetAll, GetById, GetFirst, GetLast, GetMin, GetMax, GetAllSorted (asc/desc), GetPaged, GetCount
• Transactions: several add/put/delete operations that all succeed or all roll back
• Table management: AddTable, DropTable, ClearTable, TableExists, ListTables
• Database management: InitDB, InitDBWithSchema, CloseDB, DeleteDB
• Consistent IsSuccess / ErrorMessage outputs on every action; invalid JSON or missing tables return a clear error
• Safe with multiple tabs: schema changes blocked by another tab return an error instead of hanging