Database

The Database object is the primary interface for interacting with a MIKE+ model. It allows you to open existing model databases or create new ones.

To use it, first import mikeplus:

import mikeplus as mp

Opening an Existing Database

Open an existing MIKE+ model database using mp.open(). Provide the path to the .sqlite file. You can also pass a .mupp file; MIKE+Py opens the .sqlite file with the same name in the same folder.

db = mp.open("model.sqlite")
print(db)
db.close()

The Database object is automatically opened when created. If you prefer to open it manually, use auto_open=False:

db_manual = mp.open("model.sqlite", auto_open=False)
# db_manual is not yet open
print(f"Is open: {db_manual.is_open}")
db_manual.open()
print(f"Is open: {db_manual.is_open}")
db_manual.close()

It is recommended to use a with statement, which ensures the database connection is automatically opened and closed:

with mp.open("model.sqlite") as db:
    # db is open and ready to use
    print(f"Database path: {db.db_path}")
    # db is automatically closed when exiting this block

Creating a New Database

Create a new, empty MIKE+ model database using mp.create():

db_new = mp.create("new_model.sqlite")
# A new_model.sqlite file is created
print(db_new.db_path)
db_new.close()

You can specify a spatial reference system using either projection_string or srid (but not both). MIKE+ models need a projected coordinate system, so a geographic SRID such as 4326 raises a ValueError.

# Example using the SRID for ETRS89 / UTM zone 32N
db_srid = mp.create("projected_model.sqlite", srid=25832)
print(db_srid.srid)  # 25832
print(db_srid.projection_string)
db_srid.close()

By default, mp.create() will raise a FileExistsError if the database file already exists. To overwrite an existing file, use overwrite=True.

Working with the Database

Once a Database object is opened, you can access its properties and methods.

Database File Information

The db_path property provides the path to the .sqlite database file. If a .mupp file is associated with the model, its path is available via mupp_path.

with mp.open("model.sqlite") as db:
    print(f"SQLite file: {db.db_path}")
    if db.mupp_path:
        print(f"MUPP file: {db.mupp_path}")

Creating a Project File

A MIKE+ model is a .sqlite database and a .mupp project file beside it, and MIKE+ opens models through the .mupp. mp.create() writes both. For a database that has no .mupp, for example a bare .sqlite copied from elsewhere, use ensure_mupp():

with mp.open("model.sqlite") as db:
    mupp_path = db.ensure_mupp()  # model.mupp, next to model.sqlite

It returns the existing project file if there is one and never changes it. A new one records the database’s model type and unit system, and refers to the database by a path relative to itself, so keep the two files together when you move the model.

Warning

mp.create(..., overwrite=True) deletes the .mupp of that name as well as the database. Settings MIKE+ keeps in a .mupp, such as map layers, symbology and the map’s coordinate system, are lost.

General Database Properties

Retrieve general information about the database:

with mp.open("model.sqlite") as db:
    print(f"Database version: {db.version}")
    print(f"Unit system: {db.unit_system}")
    print(f"Projection: {db.projection_string}") # Or db.srid

Scenarios

The scenarios property is a collection of the scenarios in the database. Get or set the currently active scenario using active_scenario, which takes a Scenario object rather than a name.

with mp.open("model.sqlite") as db:
    print(f"Available scenarios: {[s.name for s in db.scenarios]}")
    current_scenario = db.active_scenario
    print(f"Active scenario: {current_scenario}")

    # To change the active scenario:
    # other = db.scenarios.by_name("MyOtherScenario")
    # if other is not None:
    #     db.active_scenario = other

Active Model and Simulation Setup

The active_model property indicates the current model type (e.g., ‘CS_MIKE1D’, ‘WD_EPANET’). The active_simulation property shows the ID of the currently active simulation setup.

with mp.open("model.sqlite") as db:
    print(f"Active model type: {db.active_model}")
    print(f"Active simulation setup ID: {db.active_simulation}")

Accessing Data Tables

The tables property is your gateway to the data within the database. It returns a TableCollection object.

with mp.open("model.sqlite") as db:
    all_tables = db.tables
    # Example: list some available table names
    # print(list(all_tables.keys())[0:5])

See the Tables page for details on working with tables and their data.

Running Simulations

Execute model simulations using the run() method.

with mp.open("model.sqlite") as db:
    # This runs the currently active simulation setup
    # result_files = db.run() 
    pass # More details on the Simulations page

Refer to the Simulations page for more information on running simulations.