CREATE TABLE exercises (
    id           INTEGER PRIMARY KEY AUTOINCREMENT,
    name         TEXT NOT NULL CHECK(length(name) >= 1 AND length(name) <= 100),
    description  TEXT DEFAULT '',
    muscle_group TEXT NOT NULL CHECK(muscle_group IN (
        'brust', 'ruecken', 'schultern', 'bizeps', 'trizeps',
        'beine', 'bauch', 'ganzkoerper', 'sonstiges'
    )),
    weight_step_kg REAL NOT NULL DEFAULT 2.5 CHECK(weight_step_kg > 0),
    created_at   DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    updated_at   DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    deleted_at   DATETIME
);

CREATE INDEX idx_exercises_muscle_group ON exercises(muscle_group) WHERE deleted_at IS NULL;
CREATE INDEX idx_exercises_deleted_at ON exercises(deleted_at);