Python client

Use the mosaica package to make a Mosaica database from data frames and files, to read one from Python or a notebook, and to manage a running database through its control plane. It returns every table as a pyarrow table, which pandas and polars both read.

The notebook map needs the widget extra, mosaica[widget]. Because Map, create, open and Database are loaded only when first used, import mosaica works without anywidget or pyarrow installed.

These are the names mosaica exports:

Name	What it is	Page
connect	A function that connects to a database someone else runs, as a reader	Connecting and creating
create, open	Functions that make a new database in a directory, or open one saved there	Connecting and creating
Database	A database in a directory, which runs its own server	Connecting and creating; its methods are on the task pages
Token, login, logout, authorise, revoke	A token, and the functions that make and end one	Connecting and creating
Refusal	The exception raised when a request is refused	Connecting and creating
Control, Answer	A client for a running database's control plane, and the answer each of its route methods returns	Operating
Viewer, Selection, Sample	A reader of a database, a part of one of its views, and the points a map draws	Reading
Batches, PartialRead	The pages of a large read of records, and the exception raised when a read stops part of the way	Reading
Map	An interactive map shown in a notebook cell	The notebook map
__version__	The package's version, as a string

The package's calls return these types too. They are not imported by name.

Type	What it is	Page
Declared, DeclaredColumn	What Database.declare_columns declared	Declaring
Insert	What Database.insert handed over	Inserting and committing
Report, CommitReport, PagedReport	What Database.check and Database.commit found or did	Inserting and committing
Finding	A problem that Database.check or Database.commit found	Inserting and committing
ChangeReport	What Database.remove, suppress, unsuppress or leave did	Operating
Listening	The addresses a database's server listens on	Operating
ServeRefused	The exception raised when a server that a Database started does not report the addresses it listens on	Operating

The methods of Database are on four pages: declaring, inserting and committing, reading and operating. The rest are on connecting and creating.