DuckDB

Embedded analytics database: run SQL, insert and delete rows, and read table definitions

Signs in with: Connection details
Runs on: Cloud or On-Prem Worker
Operations: 21
Ready-made triggers: 0

Connect DuckDB

In Neblex open Connect › Connections and click New Connection.
Search for DuckDB and give the connection a clear name.
Fill in the fields. Secret values are encrypted and never shown again.
Click Test, then Create Connection.

If the system is only reachable inside your network, choose an On-Prem Worker under Test from and run the flow on that Worker. See On-Prem Workers.

Field	What to enter
Database fileRequired	The full path of the DuckDB database file on the machine where the On-Prem Worker runs.Example: `/var/lib/app/data.duckdb`
Open read-onlyOptional	Open the file for reading only, so no step using this connection can change it.
Create the file if it does not existOptional	Create an empty DuckDB database at this path when no file exists yet. Leave off to report a missing file instead.

Use it in a flow

Open a flow, open the node library and search for DuckDB.
Drag it onto the canvas and choose an Operation and your connection.
Map the operation's fields from earlier steps, or click Map with Matt.
Use Test this step to see what it returns, then save.

To start a flow from DuckDB without a ready-made trigger: a Poll for changes trigger on DuckDB with your own query passes on new or changed records.

Operations

21 operations in 3 groups. Each one is a step you can add to a flow.

Database5

Get current time`serverTime`		Return the current time as DuckDB reports it.
Get database information`databaseInfo`		Return the size, block usage, write-ahead log size and memory use of every attached database.
Get engine version`serverVersion`		Return the version and source id of the DuckDB engine that opens the file.
List attached databases`listDatabases`		List the attached databases with their file, type and whether they are read-only.
Write changes to the file`checkpoint`		Write every committed change from the write-ahead log into the database file.

Schema7

Get table definition`getTableDefinition`		Return the CREATE statement of a table or view.
Get table statistics`tableStatistics`		Return the estimated row count and column count of a table.
List schemas`listSchemas`		List the schemas of every attached database.
List table columns`listColumns`		List the columns of a table with their type, nullability, default and numeric precision.
List table constraints`listConstraints`		List the primary key, unique, foreign key, check and not-null constraints of a table with their columns.
List table indexes`listIndexes`		List the indexes of a table with their uniqueness and definition.
List tables`listTables`		List tables and views with their database, schema and type.

SQL9

Delete rows (mapped)`delete`		Delete the row matching the key columns of each record.
Execute command`command`		Execute the DuckDB INSERT, UPDATE, DELETE, COPY or DDL statement entered in the statement editor.
Execute query`query`		Execute the DuckDB query entered in the statement editor with bound :name parameters.
Insert rows (mapped)`insert`		Insert one row per record into a table you pick, mapping each column from the record.
Run SQL script`script`		Run several DuckDB statements separated by semicolons, in order and in one transaction, with bound :name parameters.
Select rows (mapped)`select`		Read rows from a table you pick: choose the columns to return, filter by the column values you map, order and limit.
Test DuckDB`ping`		Open the database file and return ok=1.
Update rows (mapped)`update`		Update the row matching the key columns of each record, setting the other mapped columns.
Upsert rows (mapped)`upsert`		Insert one row per record, or update the existing row when the key columns already match.