harlequin

A Terminal-based SQL IDE for DuckDB.

(A Harlequin is also a pretty duck.)

Installing Harlequin

After installing Python 3.8 or above, install Harlequin using pip or pipx with:

pipx install harlequin

Tip:

You can run invoke directly with pipx run anywhere that pipx is installed. For example:

• pipx run harlequin --help
• pipx run harlequin ./my.duckdb

Using Harlequin

From any shell, to open a DuckDB database file:

harlequin "path/to/duck.db"

To open an in-memory DuckDB session, run Harlequin with no arguments:

harlequin

You can also open a database in read-only mode:

harlequin -r "path/to/duck.db"

Viewing the Schema of your Database

When Harlequin is open, you can view the schema of your DuckDB database in the left sidebar. You can use your mouse or the arrow keys + enter to navigate the tree. The tree shows schemas, tables/views and their types, and columns and their types.

Editing a Query

The main query editor is a full-featured text editor, with features including syntax highlighting, auto-formatting with ctrl + ` , text selection, copy/paste, and more.

You can save the query currently in the editor with ctrl + s. You can open a query in any text or .sql file with ctrl + o.

Running a Query and Viewing Results

To run a query, press ctrl + enter. Up to 50k records will be loaded into the results pane below the query editor. When the focus is on the data pane, you can use your arrow keys or mouse to select different cells.

Exiting Harlequin

Press ctrl + q to quit and return to your shell.