CREATE TABLE metadata_cache (
    id BIGSERIAL PRIMARY KEY,
    provider TEXT NOT NULL,
    provider_id TEXT NOT NULL,
    media_type TEXT NOT NULL,
    data JSONB NOT NULL,
    cached_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    expires_at TIMESTAMPTZ NOT NULL
);

CREATE UNIQUE INDEX idx_metadata_cache_lookup ON metadata_cache (provider, provider_id);
CREATE INDEX idx_metadata_cache_expired ON metadata_cache (expires_at) WHERE expires_at < NOW();