Add view to fix deduplication

backend/sync_server/src/database/migrations/20241207143519_bootstrap.sql

@@ -10,3 +10,18 @@ CREATE TABLE IF NOT EXISTS documents (
     is_deleted BOOLEAN NOT NULL,
     PRIMARY KEY (vault_id, document_id, version_id)
 );
+
+CREATE VIEW IF NOT EXISTS latest_documents AS
+SELECT d.*
+FROM documents d
+INNER JOIN (
+    SELECT vault_id, document_id, MAX(version_id) AS max_version_id
+    FROM documents
+    GROUP BY vault_id, document_id
+) max_versions
+ON d.vault_id = max_versions.vault_id
+AND d.document_id = max_versions.document_id
+AND d.version_id = max_versions.max_version_id;
+
+CREATE INDEX IF NOT EXISTS idx_documents_vault_doc
+ON documents (vault_id, document_id);