feat: Datenmodell (SQLAlchemy) und Alembic-Migration

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

finance/alembic.ini

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+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts.
+# this is typically a path given in POSIX (e.g. forward slashes)
+# format, relative to the token %(here)s which refers to the location of this
+# ini file
+script_location = %(here)s/alembic
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.  for multiple paths, the path separator
+# is defined by "path_separator" below.
+prepend_sys_path = .
+
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python>=3.9 or backports.zoneinfo library and tzdata library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; This defaults
+# to <script_location>/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "path_separator"
+# below.
+# version_locations = %(here)s/bar:%(here)s/bat:%(here)s/alembic/versions
+
+# path_separator; This indicates what character is used to split lists of file
+# paths, including version_locations and prepend_sys_path within configparser
+# files such as alembic.ini.
+# The default rendered in new alembic.ini files is "os", which uses os.pathsep
+# to provide os-dependent path splitting.
+#
+# Note that in order to support legacy alembic.ini files, this default does NOT
+# take place if path_separator is not present in alembic.ini.  If this
+# option is omitted entirely, fallback logic is as follows:
+#
+# 1. Parsing of the version_locations option falls back to using the legacy
+#    "version_path_separator" key, which if absent then falls back to the legacy
+#    behavior of splitting on spaces and/or commas.
+# 2. Parsing of the prepend_sys_path option falls back to the legacy
+#    behavior of splitting on spaces, commas, or colons.
+#
+# Valid values for path_separator are:
+#
+# path_separator = :
+# path_separator = ;
+# path_separator = space
+# path_separator = newline
+#
+# Use os.pathsep. Default configuration used for new projects.
+path_separator = os
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# database URL.  This is consumed by the user-maintained env.py script only.
+# other means of configuring database URLs may be customized within the env.py
+# file.
+sqlalchemy.url = driver://user:pass@localhost/dbname
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = check --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration.  This is also consumed by the user-maintained
+# env.py script only.
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARNING
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARNING
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

finance/alembic/README

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+Generic single-database configuration.

finance/alembic/env.py

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+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+from app.config import get_settings
+from app.db import Base
+import app.models  # noqa: F401
+
+config.set_main_option("sqlalchemy.url", get_settings().database_url)
+target_metadata = Base.metadata
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection, target_metadata=target_metadata
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

finance/alembic/script.py.mako

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+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, Sequence[str], None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    ${downgrades if downgrades else "pass"}

finance/alembic/versions/b2b1f5a18a74_initial_schema.py

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+"""initial schema
+
+Revision ID: b2b1f5a18a74
+Revises: 
+Create Date: 2026-07-17 17:08:30.212347
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'b2b1f5a18a74'
+down_revision: Union[str, Sequence[str], None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('accounts',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('bank', sa.String(length=50), nullable=False),
+    sa.Column('iban', sa.String(length=34), nullable=False),
+    sa.Column('name', sa.String(length=100), nullable=False),
+    sa.Column('type', sa.String(length=20), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('iban')
+    )
+    op.create_table('categories',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=100), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('name')
+    )
+    op.create_table('loans',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('principal', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.Column('annual_rate_pct', sa.Numeric(precision=5, scale=2), nullable=False),
+    sa.Column('term_months', sa.Integer(), nullable=False),
+    sa.Column('payout_date', sa.Date(), nullable=False),
+    sa.Column('repayment_type', sa.String(length=20), nullable=False),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('scenarios',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('description', sa.Text(), nullable=False),
+    sa.Column('include_recurring', sa.Boolean(), nullable=False),
+    sa.Column('include_planned', sa.Boolean(), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('name')
+    )
+    op.create_table('category_rules',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('pattern', sa.String(length=200), nullable=False),
+    sa.Column('category_id', sa.Integer(), nullable=False),
+    sa.Column('priority', sa.Integer(), nullable=False),
+    sa.ForeignKeyConstraint(['category_id'], ['categories.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('planned_items',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('amount', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.Column('due', sa.Date(), nullable=False),
+    sa.Column('category_id', sa.Integer(), nullable=True),
+    sa.ForeignKeyConstraint(['category_id'], ['categories.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('projection_points',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('scenario_id', sa.Integer(), nullable=False),
+    sa.Column('day', sa.Date(), nullable=False),
+    sa.Column('balance', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.ForeignKeyConstraint(['scenario_id'], ['scenarios.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_projection_points_scenario_id'), 'projection_points', ['scenario_id'], unique=False)
+    op.create_table('projection_results',
+    sa.Column('scenario_id', sa.Integer(), nullable=False),
+    sa.Column('computed_at', sa.DateTime(), nullable=False),
+    sa.Column('low_point_date', sa.Date(), nullable=False),
+    sa.Column('low_point_balance', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.Column('below_zero_date', sa.Date(), nullable=True),
+    sa.Column('below_threshold_date', sa.Date(), nullable=True),
+    sa.ForeignKeyConstraint(['scenario_id'], ['scenarios.id'], ),
+    sa.PrimaryKeyConstraint('scenario_id')
+    )
+    op.create_table('recurring_items',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('name', sa.String(length=200), nullable=False),
+    sa.Column('amount', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.Column('rhythm', sa.String(length=20), nullable=False),
+    sa.Column('due_day', sa.Integer(), nullable=False),
+    sa.Column('start_date', sa.Date(), nullable=True),
+    sa.Column('end_date', sa.Date(), nullable=True),
+    sa.Column('category_id', sa.Integer(), nullable=True),
+    sa.ForeignKeyConstraint(['category_id'], ['categories.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('scenario_loans',
+    sa.Column('scenario_id', sa.Integer(), nullable=False),
+    sa.Column('loan_id', sa.Integer(), nullable=False),
+    sa.ForeignKeyConstraint(['loan_id'], ['loans.id'], ),
+    sa.ForeignKeyConstraint(['scenario_id'], ['scenarios.id'], ),
+    sa.PrimaryKeyConstraint('scenario_id', 'loan_id')
+    )
+    op.create_table('scenario_modifiers',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('scenario_id', sa.Integer(), nullable=False),
+    sa.Column('target_type', sa.String(length=20), nullable=False),
+    sa.Column('target_id', sa.Integer(), nullable=False),
+    sa.Column('kind', sa.String(length=20), nullable=False),
+    sa.Column('value', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.ForeignKeyConstraint(['scenario_id'], ['scenarios.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('statements',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('filename', sa.String(length=255), nullable=False),
+    sa.Column('bank', sa.String(length=50), nullable=False),
+    sa.Column('account_id', sa.Integer(), nullable=True),
+    sa.Column('period_start', sa.Date(), nullable=True),
+    sa.Column('period_end', sa.Date(), nullable=True),
+    sa.Column('opening_balance', sa.Numeric(precision=12, scale=2), nullable=True),
+    sa.Column('closing_balance', sa.Numeric(precision=12, scale=2), nullable=True),
+    sa.Column('status', sa.String(length=20), nullable=False),
+    sa.Column('error_message', sa.Text(), nullable=True),
+    sa.ForeignKeyConstraint(['account_id'], ['accounts.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('transactions',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('account_id', sa.Integer(), nullable=False),
+    sa.Column('statement_id', sa.Integer(), nullable=True),
+    sa.Column('booking_date', sa.Date(), nullable=False),
+    sa.Column('value_date', sa.Date(), nullable=True),
+    sa.Column('amount', sa.Numeric(precision=12, scale=2), nullable=False),
+    sa.Column('purpose', sa.Text(), nullable=False),
+    sa.Column('counterparty', sa.String(length=200), nullable=False),
+    sa.Column('category_id', sa.Integer(), nullable=True),
+    sa.Column('status', sa.String(length=20), nullable=False),
+    sa.Column('dedup_hash', sa.String(length=64), nullable=False),
+    sa.Column('is_duplicate', sa.Boolean(), nullable=False),
+    sa.ForeignKeyConstraint(['account_id'], ['accounts.id'], ),
+    sa.ForeignKeyConstraint(['category_id'], ['categories.id'], ),
+    sa.ForeignKeyConstraint(['statement_id'], ['statements.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_transactions_dedup_hash'), 'transactions', ['dedup_hash'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_transactions_dedup_hash'), table_name='transactions')
+    op.drop_table('transactions')
+    op.drop_table('statements')
+    op.drop_table('scenario_modifiers')
+    op.drop_table('scenario_loans')
+    op.drop_table('recurring_items')
+    op.drop_table('projection_results')
+    op.drop_index(op.f('ix_projection_points_scenario_id'), table_name='projection_points')
+    op.drop_table('projection_points')
+    op.drop_table('planned_items')
+    op.drop_table('category_rules')
+    op.drop_table('scenarios')
+    op.drop_table('loans')
+    op.drop_table('categories')
+    op.drop_table('accounts')
+    # ### end Alembic commands ###

finance/app/db.py

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+from sqlalchemy import create_engine
+from sqlalchemy.orm import DeclarativeBase, Session
+
+from app.config import get_settings
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+_engine = None
+
+
+def get_engine():
+    global _engine
+    if _engine is None:
+        _engine = create_engine(get_settings().database_url)
+    return _engine
+
+
+def get_session():
+    with Session(get_engine()) as session:
+        yield session

finance/app/models/__init__.py

@@ -0,0 +1 @@
+from app.models import tables  # noqa: F401

finance/app/models/tables.py

@@ -0,0 +1,137 @@
+from datetime import date, datetime
+from decimal import Decimal
+
+from sqlalchemy import Boolean, Date, DateTime, ForeignKey, Integer, Numeric, String, Text
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.db import Base
+
+MONEY = Numeric(12, 2)
+
+
+class Account(Base):
+    __tablename__ = "accounts"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    bank: Mapped[str] = mapped_column(String(50))
+    iban: Mapped[str] = mapped_column(String(34), unique=True)
+    name: Mapped[str] = mapped_column(String(100))
+    type: Mapped[str] = mapped_column(String(20), default="giro")
+
+
+class Category(Base):
+    __tablename__ = "categories"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(100), unique=True)
+
+
+class CategoryRule(Base):
+    __tablename__ = "category_rules"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    pattern: Mapped[str] = mapped_column(String(200))
+    category_id: Mapped[int] = mapped_column(ForeignKey("categories.id"))
+    priority: Mapped[int] = mapped_column(Integer, default=100)
+
+
+class Statement(Base):
+    __tablename__ = "statements"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    filename: Mapped[str] = mapped_column(String(255))
+    bank: Mapped[str] = mapped_column(String(50))
+    account_id: Mapped[int | None] = mapped_column(ForeignKey("accounts.id"), nullable=True)
+    period_start: Mapped[date | None] = mapped_column(Date, nullable=True)
+    period_end: Mapped[date | None] = mapped_column(Date, nullable=True)
+    opening_balance: Mapped[Decimal | None] = mapped_column(MONEY, nullable=True)
+    closing_balance: Mapped[Decimal | None] = mapped_column(MONEY, nullable=True)
+    status: Mapped[str] = mapped_column(String(20), default="draft")
+    error_message: Mapped[str | None] = mapped_column(Text, nullable=True)
+
+
+class Transaction(Base):
+    __tablename__ = "transactions"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    account_id: Mapped[int] = mapped_column(ForeignKey("accounts.id"))
+    statement_id: Mapped[int | None] = mapped_column(ForeignKey("statements.id"), nullable=True)
+    booking_date: Mapped[date] = mapped_column(Date)
+    value_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    amount: Mapped[Decimal] = mapped_column(MONEY)
+    purpose: Mapped[str] = mapped_column(Text, default="")
+    counterparty: Mapped[str] = mapped_column(String(200), default="")
+    category_id: Mapped[int | None] = mapped_column(ForeignKey("categories.id"), nullable=True)
+    status: Mapped[str] = mapped_column(String(20), default="draft")
+    dedup_hash: Mapped[str] = mapped_column(String(64), index=True)
+    is_duplicate: Mapped[bool] = mapped_column(Boolean, default=False)
+
+
+class RecurringItem(Base):
+    __tablename__ = "recurring_items"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(200))
+    amount: Mapped[Decimal] = mapped_column(MONEY)
+    rhythm: Mapped[str] = mapped_column(String(20))
+    due_day: Mapped[int] = mapped_column(Integer)
+    start_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    end_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    category_id: Mapped[int | None] = mapped_column(ForeignKey("categories.id"), nullable=True)
+
+
+class PlannedItem(Base):
+    __tablename__ = "planned_items"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(200))
+    amount: Mapped[Decimal] = mapped_column(MONEY)
+    due: Mapped[date] = mapped_column(Date)
+    category_id: Mapped[int | None] = mapped_column(ForeignKey("categories.id"), nullable=True)
+
+
+class Loan(Base):
+    __tablename__ = "loans"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(200))
+    principal: Mapped[Decimal] = mapped_column(MONEY)
+    annual_rate_pct: Mapped[Decimal] = mapped_column(Numeric(5, 2))
+    term_months: Mapped[int] = mapped_column(Integer)
+    payout_date: Mapped[date] = mapped_column(Date)
+    repayment_type: Mapped[str] = mapped_column(String(20), default="annuity")
+
+
+class Scenario(Base):
+    __tablename__ = "scenarios"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    name: Mapped[str] = mapped_column(String(200), unique=True)
+    description: Mapped[str] = mapped_column(Text, default="")
+    include_recurring: Mapped[bool] = mapped_column(Boolean, default=True)
+    include_planned: Mapped[bool] = mapped_column(Boolean, default=True)
+
+
+class ScenarioLoan(Base):
+    __tablename__ = "scenario_loans"
+    scenario_id: Mapped[int] = mapped_column(ForeignKey("scenarios.id"), primary_key=True)
+    loan_id: Mapped[int] = mapped_column(ForeignKey("loans.id"), primary_key=True)
+
+
+class ScenarioModifier(Base):
+    __tablename__ = "scenario_modifiers"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    scenario_id: Mapped[int] = mapped_column(ForeignKey("scenarios.id"))
+    target_type: Mapped[str] = mapped_column(String(20))
+    target_id: Mapped[int] = mapped_column(Integer)
+    kind: Mapped[str] = mapped_column(String(20))
+    value: Mapped[Decimal] = mapped_column(MONEY, default=Decimal("0"))
+
+
+class ProjectionPoint(Base):
+    __tablename__ = "projection_points"
+    id: Mapped[int] = mapped_column(primary_key=True)
+    scenario_id: Mapped[int] = mapped_column(ForeignKey("scenarios.id"), index=True)
+    day: Mapped[date] = mapped_column(Date)
+    balance: Mapped[Decimal] = mapped_column(MONEY)
+
+
+class ProjectionResult(Base):
+    __tablename__ = "projection_results"
+    scenario_id: Mapped[int] = mapped_column(ForeignKey("scenarios.id"), primary_key=True)
+    computed_at: Mapped[datetime] = mapped_column(DateTime)
+    low_point_date: Mapped[date] = mapped_column(Date)
+    low_point_balance: Mapped[Decimal] = mapped_column(MONEY)
+    below_zero_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    below_threshold_date: Mapped[date | None] = mapped_column(Date, nullable=True)

finance/tests/conftest.py

@@ -0,0 +1,17 @@
+import pytest
+from sqlalchemy import create_engine
+from sqlalchemy.orm import Session
+from sqlalchemy.pool import StaticPool
+
+from app.db import Base
+
+
+@pytest.fixture
+def db():
+    engine = create_engine(
+        "sqlite://", poolclass=StaticPool,
+        connect_args={"check_same_thread": False},
+    )
+    Base.metadata.create_all(engine)
+    with Session(engine) as session:
+        yield session

finance/tests/test_models.py

@@ -0,0 +1,24 @@
+from datetime import date
+from decimal import Decimal
+
+from app.models.tables import Account, Statement, Transaction
+
+
+def test_account_transaction_roundtrip(db):
+    acc = Account(bank="DKB", iban="DE02120300000000202051", name="Giro", type="giro")
+    db.add(acc)
+    db.flush()
+    st = Statement(filename="a.pdf", bank="DKB", account_id=acc.id,
+                   period_start=date(2026, 6, 1), period_end=date(2026, 6, 30),
+                   opening_balance=Decimal("100.00"), closing_balance=Decimal("50.00"),
+                   status="draft")
+    db.add(st)
+    db.flush()
+    tx = Transaction(account_id=acc.id, statement_id=st.id,
+                     booking_date=date(2026, 6, 3), value_date=date(2026, 6, 3),
+                     amount=Decimal("-50.00"), purpose="Miete Juni",
+                     counterparty="Vermieter GmbH", status="draft",
+                     dedup_hash="abc", is_duplicate=False)
+    db.add(tx)
+    db.commit()
+    assert db.query(Transaction).one().amount == Decimal("-50.00")