diff --git a/apps/backend/alembic/env.py b/apps/backend/alembic/env.py
index 7b09cae..a1a4adc 100644
--- a/apps/backend/alembic/env.py
+++ b/apps/backend/alembic/env.py
@@ -19,7 +19,7 @@ config = context.config
 if config.config_file_name is not None:
     fileConfig(config.config_file_name)
 
-config.set_main_option("sqlalchemy.url", get_settings().database_url)
+config.set_main_option("sqlalchemy.url", get_settings().database_url.replace("%", "%%"))
 
 target_metadata = Base.metadata
 
diff --git a/apps/backend/alembic/versions/e6d2026091501_create_data_schema.py b/apps/backend/alembic/versions/e6d2026091501_create_data_schema.py
new file mode 100644
index 0000000..8fb3694
--- /dev/null
+++ b/apps/backend/alembic/versions/e6d2026091501_create_data_schema.py
@@ -0,0 +1,218 @@
+"""Création des six tables Data et de l'hypertable reading.
+
+Revision ID: e6d2026091501
+Revises: 821f71be74c0
+"""
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+revision = "e6d2026091501"
+down_revision = "821f71be74c0"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table(
+        "dataset",
+        sa.Column("dataset_id", sa.BigInteger(), autoincrement=True, nullable=False),
+        sa.Column("dataset_name", sa.Text(), nullable=False),
+        sa.Column("archive_sha256", sa.String(length=64), nullable=False),
+        sa.Column("storage_uri", sa.Text(), nullable=False),
+        sa.Column("source_timezone", sa.Text(), nullable=True),
+        sa.Column(
+            "metadata", postgresql.JSONB(none_as_null=True, astext_type=sa.Text()), nullable=False
+        ),
+        sa.CheckConstraint("dataset_id > 0", name="ck_dataset_positive_id"),
+        sa.PrimaryKeyConstraint("dataset_id"),
+        sa.UniqueConstraint("archive_sha256", name="uq_dataset_archive_sha256"),
+    )
+    op.create_table(
+        "site",
+        sa.Column("site_id", sa.Text(), nullable=False),
+        sa.Column("site_name", sa.Text(), nullable=False),
+        sa.Column("site_type", sa.Text(), nullable=False),
+        sa.Column("location", sa.Text(), nullable=True),
+        sa.Column("capacity_kw", sa.Double(), nullable=True),
+        sa.Column("status", sa.Text(), nullable=True),
+        sa.PrimaryKeyConstraint("site_id"),
+    )
+    op.create_table(
+        "prediction",
+        sa.Column("prediction_id", sa.BigInteger(), autoincrement=True, nullable=False),
+        sa.Column("site_id", sa.Text(), nullable=False),
+        sa.Column(
+            "created_at",
+            sa.DateTime(timezone=True),
+            server_default=sa.text("now()"),
+            nullable=False,
+        ),
+        sa.Column("target_at", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("target_metric", sa.Text(), nullable=False),
+        sa.Column("period_minutes", sa.Integer(), nullable=True),
+        sa.Column("predicted_value", sa.Double(), nullable=True),
+        sa.Column("model_reference", sa.Text(), nullable=False),
+        sa.Column("status", sa.Text(), nullable=False),
+        sa.Column("failure_reason", sa.Text(), nullable=True),
+        sa.CheckConstraint(
+            "(status = 'available' AND predicted_value IS NOT NULL AND failure_reason IS NULL) OR (status IN ('insufficient_data', 'error') AND predicted_value IS NULL AND failure_reason IS NOT NULL)",
+            name="ck_prediction_status",
+        ),
+        sa.CheckConstraint(
+            "target_metric <> 'consumption_kwh' OR period_minutes IS NOT NULL",
+            name="ck_prediction_energy_period",
+        ),
+        sa.CheckConstraint(
+            "target_metric IN ('consumption_kwh', 'consumption_kw')", name="ck_prediction_metric"
+        ),
+        sa.CheckConstraint(
+            "period_minutes IS NULL OR period_minutes > 0", name="ck_prediction_period"
+        ),
+        sa.ForeignKeyConstraint(
+            ["site_id"], ["site.site_id"], name="fk_prediction_site", ondelete="RESTRICT"
+        ),
+        sa.PrimaryKeyConstraint("prediction_id"),
+        sa.UniqueConstraint("prediction_id", "site_id", name="uq_prediction_id_site"),
+    )
+    op.create_index(
+        "ix_prediction_site_target", "prediction", ["site_id", "target_at"], unique=False
+    )
+    op.create_table(
+        "reading",
+        sa.Column("reading_id", sa.BigInteger(), autoincrement=True, nullable=False),
+        sa.Column("site_id", sa.Text(), nullable=False),
+        sa.Column("timestamp", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("source", sa.Text(), nullable=False),
+        sa.Column("dataset_id", sa.BigInteger(), nullable=True),
+        sa.Column("consumption_kw", sa.Double(), nullable=True),
+        sa.Column("consumption_kwh", sa.Double(), nullable=True),
+        sa.Column("consumption_euros", sa.Numeric(precision=14, scale=2), nullable=True),
+        sa.Column("voltage_v", sa.Double(), nullable=True),
+        sa.Column("current_a", sa.Double(), nullable=True),
+        sa.Column("power_factor", sa.Double(), nullable=True),
+        sa.Column("temperature_celsius", sa.Double(), nullable=True),
+        sa.Column("humidity_percent", sa.Double(), nullable=True),
+        sa.Column("solar_irradiance_wm2", sa.Double(), nullable=True),
+        sa.Column("is_working_hours", sa.Boolean(), nullable=True),
+        sa.Column("data_quality", sa.Text(), nullable=True),
+        sa.Column("null_reasons", postgresql.ARRAY(sa.Text()), nullable=True),
+        sa.Column(
+            "imputed_values", postgresql.JSONB(none_as_null=True, astext_type=sa.Text()), nullable=True
+        ),
+        sa.Column("imputation_method", sa.Text(), nullable=True),
+        sa.Column(
+            "ingested_at",
+            sa.DateTime(timezone=True),
+            server_default=sa.text("now()"),
+            nullable=False,
+        ),
+        sa.Column(
+            "raw_data", postgresql.JSONB(none_as_null=True, astext_type=sa.Text()), nullable=False
+        ),
+        sa.CheckConstraint(
+            "(source = 'csv' AND dataset_id IS NOT NULL) OR (source IN ('api_current', 'api_history') AND dataset_id IS NULL)",
+            name="ck_reading_dataset_source",
+        ),
+        sa.CheckConstraint(
+            "data_quality IS NULL OR data_quality IN ('good', 'partial', 'degraded', 'critical')",
+            name="ck_reading_quality",
+        ),
+        sa.CheckConstraint(
+            "source IN ('csv', 'api_current', 'api_history')", name="ck_reading_source"
+        ),
+        sa.CheckConstraint(
+            "(imputed_values IS NULL AND imputation_method IS NULL) OR (imputed_values IS NOT NULL AND imputation_method IS NOT NULL)",
+            name="ck_reading_imputation",
+        ),
+        sa.ForeignKeyConstraint(
+            ["dataset_id"], ["dataset.dataset_id"], name="fk_reading_dataset", ondelete="RESTRICT"
+        ),
+        sa.ForeignKeyConstraint(
+            ["site_id"], ["site.site_id"], name="fk_reading_site", ondelete="RESTRICT"
+        ),
+        sa.PrimaryKeyConstraint("reading_id", "timestamp"),
+    )
+    op.create_index("ix_reading_dataset_id", "reading", ["dataset_id"], unique=False)
+    op.create_index(
+        "ix_reading_site_timestamp", "reading", ["site_id", "timestamp"], unique=False
+    )
+    op.create_index(
+        "uq_reading_source",
+        "reading",
+        ["site_id", "timestamp", "source", sa.literal_column("coalesce(dataset_id, 0)")],
+        unique=True,
+    )
+    op.execute(
+        "SELECT create_hypertable('reading', by_range('timestamp'), create_default_indexes => FALSE)"
+    )
+    op.create_table(
+        "alert",
+        sa.Column("alert_id", sa.BigInteger(), autoincrement=True, nullable=False),
+        sa.Column("source_alert_id", sa.Text(), nullable=False),
+        sa.Column("site_id", sa.Text(), nullable=False),
+        sa.Column("source", sa.Text(), nullable=False),
+        sa.Column("timestamp", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("type", sa.Text(), nullable=False),
+        sa.Column("severity", sa.Text(), nullable=False),
+        sa.Column("message", sa.Text(), nullable=False),
+        sa.Column("value", sa.Double(), nullable=True),
+        sa.Column("threshold", sa.Double(), nullable=True),
+        sa.Column("metric", sa.Text(), nullable=True),
+        sa.Column("prediction_id", sa.BigInteger(), nullable=True),
+        sa.Column(
+            "raw_data", postgresql.JSONB(none_as_null=True, astext_type=sa.Text()), nullable=False
+        ),
+        sa.CheckConstraint(
+            "severity IN ('low', 'medium', 'high', 'critical')", name="ck_alert_severity"
+        ),
+        sa.CheckConstraint("source IN ('api_mock', 'enervision')", name="ck_alert_source"),
+        sa.CheckConstraint(
+            "type IN ('spike', 'threshold', 'anomaly', 'outage', 'sensor')", name="ck_alert_type"
+        ),
+        sa.ForeignKeyConstraint(
+            ["prediction_id", "site_id"],
+            ["prediction.prediction_id", "prediction.site_id"],
+            name="fk_alert_prediction_site",
+            ondelete="RESTRICT",
+        ),
+        sa.ForeignKeyConstraint(
+            ["site_id"], ["site.site_id"], name="fk_alert_site", ondelete="RESTRICT"
+        ),
+        sa.PrimaryKeyConstraint("alert_id"),
+        sa.UniqueConstraint(
+            "source", "site_id", "source_alert_id", name="uq_alert_source_reference"
+        ),
+    )
+    op.create_index("ix_alert_site_timestamp", "alert", ["site_id", "timestamp"], unique=False)
+    op.create_table(
+        "recommendation",
+        sa.Column("recommendation_id", sa.BigInteger(), autoincrement=True, nullable=False),
+        sa.Column("alert_id", sa.BigInteger(), nullable=False),
+        sa.Column("action", sa.Text(), nullable=False),
+        sa.Column("explanation", sa.Text(), nullable=False),
+        sa.Column("rule_reference", sa.Text(), nullable=False),
+        sa.Column(
+            "created_at",
+            sa.DateTime(timezone=True),
+            server_default=sa.text("now()"),
+            nullable=False,
+        ),
+        sa.ForeignKeyConstraint(
+            ["alert_id"], ["alert.alert_id"], name="fk_recommendation_alert", ondelete="RESTRICT"
+        ),
+        sa.PrimaryKeyConstraint("recommendation_id"),
+        sa.UniqueConstraint("alert_id", "rule_reference", name="uq_recommendation_alert_rule"),
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    op.drop_table("recommendation")
+    op.drop_table("alert")
+    op.drop_table("reading")
+    op.drop_table("prediction")
+    op.drop_table("site")
+    op.drop_table("dataset")
diff --git a/apps/backend/app/models/__init__.py b/apps/backend/app/models/__init__.py
index 9e65265..10a5ecb 100644
--- a/apps/backend/app/models/__init__.py
+++ b/apps/backend/app/models/__init__.py
@@ -2,8 +2,20 @@
 # --autogenerate`, qui générerait alors un drop de sa table.
 
 from app.models.audit_log import AuditLog
+from app.models.energy import Alert, Dataset, Prediction, Reading, Recommendation, Site
 from app.models.login_attempt import LoginAttempt
 from app.models.refresh_token import RefreshToken
 from app.models.user import AppUser
 
-__all__ = ["AppUser", "AuditLog", "LoginAttempt", "RefreshToken"]
+__all__ = [
+    "Alert",
+    "AppUser",
+    "AuditLog",
+    "Dataset",
+    "LoginAttempt",
+    "Prediction",
+    "Reading",
+    "Recommendation",
+    "RefreshToken",
+    "Site",
+]
diff --git a/apps/backend/app/models/energy.py b/apps/backend/app/models/energy.py
new file mode 100644
index 0000000..285ad26
--- /dev/null
+++ b/apps/backend/app/models/energy.py
@@ -0,0 +1,210 @@
+"""Tables du modèle de données EnerVision (CSV, API Mock et résultats ML)."""
+
+from datetime import datetime
+from decimal import Decimal
+from typing import Any
+
+from sqlalchemy import (
+    BigInteger,
+    Boolean,
+    CheckConstraint,
+    DateTime,
+    Double,
+    ForeignKey,
+    ForeignKeyConstraint,
+    Index,
+    Integer,
+    Numeric,
+    String,
+    Text,
+    UniqueConstraint,
+    func,
+    text,
+)
+from sqlalchemy.dialects.postgresql import ARRAY, JSONB
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.db.base import Base
+
+
+class Dataset(Base):
+    __tablename__ = "dataset"
+    __table_args__ = (
+        CheckConstraint("dataset_id > 0", name="ck_dataset_positive_id"),
+        UniqueConstraint("archive_sha256", name="uq_dataset_archive_sha256"),
+    )
+
+    dataset_id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    dataset_name: Mapped[str] = mapped_column(Text)
+    archive_sha256: Mapped[str] = mapped_column(String(64))
+    storage_uri: Mapped[str] = mapped_column(Text)
+    source_timezone: Mapped[str | None] = mapped_column(Text)
+    # "metadata" est réservé par SQLAlchemy ; le nom SQL reste inchangé.
+    dataset_metadata: Mapped[dict[str, Any]] = mapped_column("metadata", JSONB(none_as_null=True))
+
+
+class Site(Base):
+    __tablename__ = "site"
+
+    site_id: Mapped[str] = mapped_column(Text, primary_key=True)
+    site_name: Mapped[str] = mapped_column(Text)
+    site_type: Mapped[str] = mapped_column(Text)
+    location: Mapped[str | None] = mapped_column(Text)
+    capacity_kw: Mapped[float | None] = mapped_column(Double)
+    status: Mapped[str | None] = mapped_column(Text)
+
+
+class Reading(Base):
+    __tablename__ = "reading"
+    __table_args__ = (
+        CheckConstraint(
+            "source IN ('csv', 'api_current', 'api_history')", name="ck_reading_source"
+        ),
+        CheckConstraint(
+            "(source = 'csv' AND dataset_id IS NOT NULL) OR "
+            "(source IN ('api_current', 'api_history') AND dataset_id IS NULL)",
+            name="ck_reading_dataset_source",
+        ),
+        CheckConstraint(
+            "data_quality IS NULL OR data_quality IN ('good', 'partial', 'degraded', 'critical')",
+            name="ck_reading_quality",
+        ),
+        CheckConstraint(
+            "(imputed_values IS NULL AND imputation_method IS NULL) OR "
+            "(imputed_values IS NOT NULL AND imputation_method IS NOT NULL)",
+            name="ck_reading_imputation",
+        ),
+        Index("ix_reading_site_timestamp", "site_id", "timestamp"),
+        Index("ix_reading_dataset_id", "dataset_id"),
+    )
+
+    reading_id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    site_id: Mapped[str] = mapped_column(
+        Text, ForeignKey("site.site_id", name="fk_reading_site", ondelete="RESTRICT")
+    )
+    timestamp: Mapped[datetime] = mapped_column(DateTime(timezone=True), primary_key=True)
+    source: Mapped[str] = mapped_column(Text)
+    dataset_id: Mapped[int | None] = mapped_column(
+        BigInteger,
+        ForeignKey("dataset.dataset_id", name="fk_reading_dataset", ondelete="RESTRICT"),
+    )
+    consumption_kw: Mapped[float | None] = mapped_column(Double)
+    consumption_kwh: Mapped[float | None] = mapped_column(Double)
+    consumption_euros: Mapped[Decimal | None] = mapped_column(Numeric(14, 2))
+    voltage_v: Mapped[float | None] = mapped_column(Double)
+    current_a: Mapped[float | None] = mapped_column(Double)
+    power_factor: Mapped[float | None] = mapped_column(Double)
+    temperature_celsius: Mapped[float | None] = mapped_column(Double)
+    humidity_percent: Mapped[float | None] = mapped_column(Double)
+    solar_irradiance_wm2: Mapped[float | None] = mapped_column(Double)
+    is_working_hours: Mapped[bool | None] = mapped_column(Boolean)
+    data_quality: Mapped[str | None] = mapped_column(Text)
+    null_reasons: Mapped[list[str] | None] = mapped_column(ARRAY(Text))
+    imputed_values: Mapped[dict[str, Any] | None] = mapped_column(JSONB(none_as_null=True))
+    imputation_method: Mapped[str | None] = mapped_column(Text)
+    ingested_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now()
+    )
+    raw_data: Mapped[dict[str, Any]] = mapped_column(JSONB(none_as_null=True))
+
+
+Index(
+    "uq_reading_source",
+    Reading.site_id,
+    Reading.timestamp,
+    Reading.source,
+    func.coalesce(Reading.dataset_id, text("0")),
+    unique=True,
+)
+
+
+class Prediction(Base):
+    __tablename__ = "prediction"
+    __table_args__ = (
+        UniqueConstraint("prediction_id", "site_id", name="uq_prediction_id_site"),
+        Index("ix_prediction_site_target", "site_id", "target_at"),
+        CheckConstraint(
+            "target_metric IN ('consumption_kwh', 'consumption_kw')",
+            name="ck_prediction_metric",
+        ),
+        CheckConstraint(
+            "period_minutes IS NULL OR period_minutes > 0", name="ck_prediction_period"
+        ),
+        CheckConstraint(
+            "target_metric <> 'consumption_kwh' OR period_minutes IS NOT NULL",
+            name="ck_prediction_energy_period",
+        ),
+        CheckConstraint(
+            "(status = 'available' AND predicted_value IS NOT NULL AND failure_reason IS NULL) OR "
+            "(status IN ('insufficient_data', 'error') AND predicted_value IS NULL "
+            "AND failure_reason IS NOT NULL)",
+            name="ck_prediction_status",
+        ),
+    )
+
+    prediction_id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    site_id: Mapped[str] = mapped_column(
+        Text, ForeignKey("site.site_id", name="fk_prediction_site", ondelete="RESTRICT")
+    )
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
+    target_at: Mapped[datetime] = mapped_column(DateTime(timezone=True))
+    target_metric: Mapped[str] = mapped_column(Text)
+    period_minutes: Mapped[int | None] = mapped_column(Integer)
+    predicted_value: Mapped[float | None] = mapped_column(Double)
+    model_reference: Mapped[str] = mapped_column(Text)
+    status: Mapped[str] = mapped_column(Text)
+    failure_reason: Mapped[str | None] = mapped_column(Text)
+
+
+class Alert(Base):
+    __tablename__ = "alert"
+    __table_args__ = (
+        UniqueConstraint("source", "site_id", "source_alert_id", name="uq_alert_source_reference"),
+        Index("ix_alert_site_timestamp", "site_id", "timestamp"),
+        ForeignKeyConstraint(
+            ["prediction_id", "site_id"],
+            ["prediction.prediction_id", "prediction.site_id"],
+            name="fk_alert_prediction_site",
+            ondelete="RESTRICT",
+        ),
+        CheckConstraint("source IN ('api_mock', 'enervision')", name="ck_alert_source"),
+        CheckConstraint(
+            "type IN ('spike', 'threshold', 'anomaly', 'outage', 'sensor')", name="ck_alert_type"
+        ),
+        CheckConstraint(
+            "severity IN ('low', 'medium', 'high', 'critical')", name="ck_alert_severity"
+        ),
+    )
+
+    alert_id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    source_alert_id: Mapped[str] = mapped_column(Text)
+    site_id: Mapped[str] = mapped_column(
+        Text, ForeignKey("site.site_id", name="fk_alert_site", ondelete="RESTRICT")
+    )
+    source: Mapped[str] = mapped_column(Text)
+    timestamp: Mapped[datetime] = mapped_column(DateTime(timezone=True))
+    type: Mapped[str] = mapped_column(Text)
+    severity: Mapped[str] = mapped_column(Text)
+    message: Mapped[str] = mapped_column(Text)
+    value: Mapped[float | None] = mapped_column(Double)
+    threshold: Mapped[float | None] = mapped_column(Double)
+    metric: Mapped[str | None] = mapped_column(Text)
+    prediction_id: Mapped[int | None] = mapped_column(BigInteger)
+    raw_data: Mapped[dict[str, Any]] = mapped_column(JSONB(none_as_null=True))
+
+
+class Recommendation(Base):
+    __tablename__ = "recommendation"
+    __table_args__ = (
+        UniqueConstraint("alert_id", "rule_reference", name="uq_recommendation_alert_rule"),
+    )
+
+    recommendation_id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    alert_id: Mapped[int] = mapped_column(
+        BigInteger,
+        ForeignKey("alert.alert_id", name="fk_recommendation_alert", ondelete="RESTRICT"),
+    )
+    action: Mapped[str] = mapped_column(Text)
+    explanation: Mapped[str] = mapped_column(Text)
+    rule_reference: Mapped[str] = mapped_column(Text)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
diff --git a/apps/backend/tests/db/test_data_schema.py b/apps/backend/tests/db/test_data_schema.py
new file mode 100644
index 0000000..c564042
--- /dev/null
+++ b/apps/backend/tests/db/test_data_schema.py
@@ -0,0 +1,261 @@
+from collections.abc import AsyncIterator
+from datetime import UTC, datetime
+from uuid import uuid4
+
+import pytest
+from sqlalchemy import insert, select, text
+from sqlalchemy.engine import make_url
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.ext.asyncio import AsyncConnection, create_async_engine
+
+from app.core.config import get_settings
+from app.models.energy import Alert, Dataset, Prediction, Reading, Recommendation, Site
+
+pytestmark = pytest.mark.integration
+MOMENT = datetime(2024, 1, 1, tzinfo=UTC)
+
+
+@pytest.fixture
+async def data_connection() -> AsyncIterator[AsyncConnection]:
+    url = make_url(get_settings().database_url)
+    if url.database != "enervision_test":
+        pytest.fail("Ces tests exigent DATABASE_URL vers enervision_test.")
+    engine = create_async_engine(url)
+    try:
+        async with engine.connect() as connection:
+            transaction = await connection.begin()
+            try:
+                yield connection
+            finally:
+                await transaction.rollback()
+    finally:
+        await engine.dispose()
+
+
+@pytest.fixture
+async def data_site(data_connection: AsyncConnection) -> str:
+    site_id = f"TEST-{uuid4()}"
+    await data_connection.execute(
+        insert(Site).values(site_id=site_id, site_name="Site de test", site_type="office")
+    )
+    return site_id
+
+
+async def test_reading_is_a_time_hypertable_when_migrated(
+    data_connection: AsyncConnection,
+) -> None:
+    query = text(
+        "SELECT column_name FROM timescaledb_information.dimensions "
+        "WHERE hypertable_schema = 'public' AND hypertable_name = 'reading'"
+    )
+
+    result = await data_connection.execute(query)
+
+    assert result.scalars().all() == ["timestamp"]
+
+
+async def test_reading_preserves_null_and_zero_when_inserted(
+    data_connection: AsyncConnection, data_site: str
+) -> None:
+    statement = insert(Reading).values(
+        site_id=data_site,
+        timestamp=MOMENT,
+        source="api_current",
+        consumption_kw=None,
+        consumption_kwh=0,
+        data_quality="partial",
+        null_reasons=["sensor_failure"],
+        raw_data={"consumption_kw": None},
+        imputed_values=None,
+        imputation_method=None,
+    )
+
+    await data_connection.execute(statement)
+    result = (
+        await data_connection.execute(
+            select(
+                Reading.consumption_kw,
+                Reading.consumption_kwh,
+                Reading.raw_data,
+                Reading.imputed_values,
+            ).where(Reading.site_id == data_site)
+        )
+    ).one()
+
+    assert tuple(result) == (None, 0, {"consumption_kw": None}, None)
+
+
+@pytest.mark.parametrize("source", ["csv", "api_current", "api_history"])
+async def test_duplicate_reading_is_rejected_when_key_matches(
+    data_connection: AsyncConnection, data_site: str, source: str
+) -> None:
+    dataset_id = None
+    if source == "csv":
+        dataset_id = (
+            await data_connection.execute(
+                insert(Dataset.__table__)
+                .values(
+                    dataset_name="Archive de test",
+                    archive_sha256=uuid4().hex + uuid4().hex,
+                    storage_uri="test://archive",
+                    metadata={},
+                )
+                .returning(Dataset.dataset_id)
+            )
+        ).scalar_one()
+    statement = insert(Reading).values(
+        site_id=data_site,
+        timestamp=MOMENT,
+        source=source,
+        dataset_id=dataset_id,
+        raw_data={},
+    )
+    await data_connection.execute(statement)
+
+    with pytest.raises(IntegrityError):
+        async with data_connection.begin_nested():
+            await data_connection.execute(statement)
+
+
+@pytest.mark.parametrize(
+    "changes",
+    [
+        {"source": "csv"},
+        {"source": "unknown"},
+        {"site_id": "UNKNOWN-SITE"},
+        {"data_quality": "unknown"},
+        {"imputed_values": {"consumption_kw": 12}},
+        {"imputation_method": "mean-v1"},
+    ],
+    ids=[
+        "csv_sans_dataset",
+        "source_inconnue",
+        "site_absent",
+        "qualite_inconnue",
+        "imputation_sans_methode",
+        "methode_sans_imputation",
+    ],
+)
+async def test_invalid_reading_is_rejected_when_constraints_fail(
+    data_connection: AsyncConnection, data_site: str, changes: dict[str, object]
+) -> None:
+    values: dict[str, object] = {
+        "site_id": data_site,
+        "timestamp": MOMENT,
+        "source": "api_current",
+        "raw_data": {},
+    }
+    values.update(changes)
+
+    with pytest.raises(IntegrityError):
+        async with data_connection.begin_nested():
+            await data_connection.execute(insert(Reading).values(**values))
+
+
+async def test_prediction_requires_period_when_energy_is_predicted(
+    data_connection: AsyncConnection, data_site: str
+) -> None:
+    statement = insert(Prediction).values(
+        site_id=data_site,
+        target_at=MOMENT,
+        target_metric="consumption_kwh",
+        predicted_value=12,
+        status="available",
+        model_reference="test-model/1",
+    )
+
+    with pytest.raises(IntegrityError):
+        async with data_connection.begin_nested():
+            await data_connection.execute(statement)
+
+
+async def test_unavailable_prediction_preserves_null_when_inserted(
+    data_connection: AsyncConnection, data_site: str
+) -> None:
+    statement = (
+        insert(Prediction)
+        .values(
+            site_id=data_site,
+            target_at=MOMENT,
+            target_metric="consumption_kw",
+            status="insufficient_data",
+            failure_reason="Historique trop court",
+            model_reference="test-model/1",
+        )
+        .returning(Prediction.predicted_value)
+    )
+
+    value = (await data_connection.execute(statement)).scalar_one()
+
+    assert value is None
+
+
+async def test_alert_rejects_prediction_when_site_differs(
+    data_connection: AsyncConnection, data_site: str
+) -> None:
+    other_site = f"TEST-{uuid4()}"
+    await data_connection.execute(
+        insert(Site).values(site_id=other_site, site_name="Autre site", site_type="office")
+    )
+    prediction_id = (
+        await data_connection.execute(
+            insert(Prediction)
+            .values(
+                site_id=data_site,
+                target_at=MOMENT,
+                target_metric="consumption_kw",
+                predicted_value=12,
+                status="available",
+                model_reference="test-model/1",
+            )
+            .returning(Prediction.prediction_id)
+        )
+    ).scalar_one()
+
+    with pytest.raises(IntegrityError):
+        async with data_connection.begin_nested():
+            await data_connection.execute(
+                insert(Alert).values(
+                    source_alert_id=str(uuid4()),
+                    site_id=other_site,
+                    source="enervision",
+                    timestamp=MOMENT,
+                    type="spike",
+                    severity="high",
+                    message="Test",
+                    prediction_id=prediction_id,
+                    raw_data={},
+                )
+            )
+
+
+async def test_recommendation_is_unique_when_alert_and_rule_match(
+    data_connection: AsyncConnection, data_site: str
+) -> None:
+    alert_id = (
+        await data_connection.execute(
+            insert(Alert)
+            .values(
+                source_alert_id=str(uuid4()),
+                site_id=data_site,
+                source="api_mock",
+                timestamp=MOMENT,
+                type="spike",
+                severity="high",
+                message="Test",
+                raw_data={},
+            )
+            .returning(Alert.alert_id)
+        )
+    ).scalar_one()
+    statement = insert(Recommendation).values(
+        alert_id=alert_id,
+        action="Vérifier la consommation",
+        explanation="Pic détecté",
+        rule_reference="spike-v1",
+    )
+    await data_connection.execute(statement)
+
+    with pytest.raises(IntegrityError):
+        async with data_connection.begin_nested():
+            await data_connection.execute(statement)