syncthing/internal/db/sqlite/sql/schema/folder/50-blocks.sql

-- Copyright (C) 2025 The Syncthing Authors.
--
-- This Source Code Form is subject to the terms of the Mozilla Public
-- License, v. 2.0. If a copy of the MPL was not distributed with this file,
-- You can obtain one at https://mozilla.org/MPL/2.0/.

-- Block lists
--
-- The block lists are extracted from FileInfos and stored separately. This
-- reduces the database size by reusing the same block list entry for all
-- devices announcing the same file. Doing it for all block lists instead of
-- using a size cutoff simplifies queries. Block lists are garbage collected
-- "manually", not using a trigger as that was too performance impacting.
CREATE TABLE IF NOT EXISTS blocklists (
    blocklist_hash BLOB NOT NULL PRIMARY KEY,
    blprotobuf BLOB NOT NULL
) STRICT, WITHOUT ROWID
;

-- Blocks
--
-- For all local files we store the blocks individually for quick lookup. A
-- given block can exist in multiple blocklists and at multiple offsets in a
-- blocklist. We eschew most indexes here as inserting millions of blocks is
-- common and performance is critical.
CREATE TABLE IF NOT EXISTS blocks (
    hash BLOB NOT NULL,
    blocklist_hash BLOB NOT NULL,
    idx INTEGER NOT NULL,
    offset INTEGER NOT NULL,
    size INTEGER NOT NULL,
    PRIMARY KEY(hash, blocklist_hash, idx)
) STRICT, WITHOUT ROWID
;