1CREATE TABLE IF NOT EXISTS "observed_buffer_edits" (
 2    "user_id" INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
 3    "buffer_id" INTEGER NOT NULL REFERENCES buffers (id) ON DELETE CASCADE,
 4    "epoch" INTEGER NOT NULL,
 5    "lamport_timestamp" INTEGER NOT NULL,
 6    "replica_id" INTEGER NOT NULL,
 7    PRIMARY KEY (user_id, buffer_id)
 8);
 9
10CREATE UNIQUE INDEX "index_observed_buffer_user_and_buffer_id" ON "observed_buffer_edits" ("user_id", "buffer_id");
11
12CREATE TABLE IF NOT EXISTS "observed_channel_messages" (
13    "user_id" INTEGER NOT NULL REFERENCES users (id) ON DELETE CASCADE,
14    "channel_id" INTEGER NOT NULL REFERENCES channels (id) ON DELETE CASCADE,
15    "channel_message_id" INTEGER NOT NULL,
16    PRIMARY KEY (user_id, channel_id)
17);
18
19CREATE UNIQUE INDEX "index_observed_channel_messages_user_and_channel_id" ON "observed_channel_messages" ("user_id", "channel_id");