diff --git a/cmd/ferretdb/main.go b/cmd/ferretdb/main.go
index bcfd8e3d7a0f..0e6ca88db610 100644
--- a/cmd/ferretdb/main.go
+++ b/cmd/ferretdb/main.go
@@ -101,6 +101,7 @@ var cli struct {
 		} `embed:"" prefix:"capped-cleanup-"`
 
 		EnableNewAuth bool `default:"false" help:"Experimental: enable new authentication."`
+		BatchSize     int  `default:"100"   help:"Experimental: maximum insertion batch size."`
 
 		Telemetry struct {
 			URL            string        `default:"https://beacon.ferretdb.com/" help:"Telemetry: reporting URL."`
@@ -412,6 +413,7 @@ func run() {
 			CappedCleanupInterval:   cli.Test.CappedCleanup.Interval,
 			CappedCleanupPercentage: cli.Test.CappedCleanup.Percentage,
 			EnableNewAuth:           cli.Test.EnableNewAuth,
+			BatchSize:               cli.Test.BatchSize,
 		},
 	})
 	if err != nil {
diff --git a/integration/setup/listener.go b/integration/setup/listener.go
index e795d810575d..307e503bd6e1 100644
--- a/integration/setup/listener.go
+++ b/integration/setup/listener.go
@@ -185,6 +185,7 @@ func setupListener(tb testtb.TB, ctx context.Context, logger *zap.Logger, opts *
 			CappedCleanupPercentage: opts.CappedCleanupPercentage,
 			CappedCleanupInterval:   opts.CappedCleanupInterval,
 			EnableNewAuth:           true,
+			BatchSize:               *batchSizeF,
 		},
 	}
 	h, closeBackend, err := registry.NewHandler(handler, handlerOpts)
diff --git a/integration/setup/setup.go b/integration/setup/setup.go
index 6cd474928555..2bcee1be3948 100644
--- a/integration/setup/setup.go
+++ b/integration/setup/setup.go
@@ -56,6 +56,8 @@ var (
 	mysqlURLF      = flag.String("mysql-url", "", "in-process FerretDB: MySQL URL for 'mysql' handler.")
 	hanaURLF       = flag.String("hana-url", "", "in-process FerretDB: Hana URL for 'hana' handler.")
 
+	batchSizeF = flag.Int("batch-size", 100, "maximum insertion batch size")
+
 	compatURLF = flag.String("compat-url", "", "compat system's (MongoDB) URL for compatibility tests; if empty, they are skipped")
 
 	benchDocsF = flag.Int("bench-docs", 1000, "benchmarks: number of documents to generate per iteration")
diff --git a/internal/backends/hana/backend.go b/internal/backends/hana/backend.go
index e396c978c3f5..d8d759153e24 100644
--- a/internal/backends/hana/backend.go
+++ b/internal/backends/hana/backend.go
@@ -37,9 +37,10 @@ type backend struct {
 //
 //nolint:vet // for readability
 type NewBackendParams struct {
-	URI string
-	L   *zap.Logger
-	P   *state.Provider
+	URI       string
+	L         *zap.Logger
+	P         *state.Provider
+	BatchSize int
 }
 
 // NewBackend creates a new Backend.
@@ -50,6 +51,7 @@ func NewBackend(params *NewBackendParams) (backends.Backend, error) {
 	}
 
 	hdb := fsql.WrapDB(db, "hana", params.L)
+	hdb.BatchSize = params.BatchSize
 
 	return backends.BackendContract(&backend{
 		hdb: hdb,
diff --git a/internal/backends/helpers_test.go b/internal/backends/helpers_test.go
index 7f3ebd825f26..ef8fe5930809 100644
--- a/internal/backends/helpers_test.go
+++ b/internal/backends/helpers_test.go
@@ -53,9 +53,10 @@ func testBackends(t *testing.T) map[string]*testBackend {
 		require.NoError(t, err)
 
 		b, err := postgresql.NewBackend(&postgresql.NewBackendParams{
-			URI: testutil.TestPostgreSQLURI(t, context.TODO(), ""),
-			L:   l.Named("postgresql"),
-			P:   sp,
+			URI:       testutil.TestPostgreSQLURI(t, context.TODO(), ""),
+			L:         l.Named("postgresql"),
+			P:         sp,
+			BatchSize: 1000,
 		})
 		require.NoError(t, err)
 		t.Cleanup(b.Close)
@@ -71,9 +72,10 @@ func testBackends(t *testing.T) map[string]*testBackend {
 		require.NoError(t, err)
 
 		b, err := sqlite.NewBackend(&sqlite.NewBackendParams{
-			URI: testutil.TestSQLiteURI(t, ""),
-			L:   l.Named("sqlite"),
-			P:   sp,
+			URI:       testutil.TestSQLiteURI(t, ""),
+			L:         l.Named("sqlite"),
+			P:         sp,
+			BatchSize: 100,
 		})
 		require.NoError(t, err)
 		t.Cleanup(b.Close)
diff --git a/internal/backends/postgresql/backend.go b/internal/backends/postgresql/backend.go
index 9aed280fb6cc..d9de166b3e16 100644
--- a/internal/backends/postgresql/backend.go
+++ b/internal/backends/postgresql/backend.go
@@ -37,15 +37,16 @@ type backend struct {
 //
 //nolint:vet // for readability
 type NewBackendParams struct {
-	URI string
-	L   *zap.Logger
-	P   *state.Provider
-	_   struct{} // prevent unkeyed literals
+	URI       string
+	L         *zap.Logger
+	P         *state.Provider
+	BatchSize int
+	_         struct{} // prevent unkeyed literals
 }
 
 // NewBackend creates a new Backend.
 func NewBackend(params *NewBackendParams) (backends.Backend, error) {
-	r, err := metadata.NewRegistry(params.URI, params.L, params.P)
+	r, err := metadata.NewRegistry(params.URI, params.BatchSize, params.L, params.P)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/backends/postgresql/collection.go b/internal/backends/postgresql/collection.go
index 66f9214eed8f..bf4fd59d4518 100644
--- a/internal/backends/postgresql/collection.go
+++ b/internal/backends/postgresql/collection.go
@@ -134,8 +134,10 @@ func (c *collection) InsertAll(ctx context.Context, params *backends.InsertAllPa
 	}
 
 	err = pool.InTransaction(ctx, p, func(tx pgx.Tx) error {
-		// TODO https://github.com/FerretDB/FerretDB/issues/3708
-		const batchSize = 100
+		batchSize := c.r.BatchSize
+		if batchSize < 1 {
+			panic("batch-size should be greater or equal to 1")
+		}
 
 		var batch []*types.Document
 		docs := params.Docs
diff --git a/internal/backends/postgresql/database_test.go b/internal/backends/postgresql/database_test.go
index 99840811f95c..1f4c72685a03 100644
--- a/internal/backends/postgresql/database_test.go
+++ b/internal/backends/postgresql/database_test.go
@@ -40,9 +40,10 @@ func TestDatabaseStats(t *testing.T) {
 	require.NoError(t, err)
 
 	params := NewBackendParams{
-		URI: testutil.TestPostgreSQLURI(t, ctx, ""),
-		L:   testutil.Logger(t),
-		P:   sp,
+		URI:       testutil.TestPostgreSQLURI(t, ctx, ""),
+		L:         testutil.Logger(t),
+		P:         sp,
+		BatchSize: 1000,
 	}
 	b, err := NewBackend(&params)
 	require.NoError(t, err)
diff --git a/internal/backends/postgresql/metadata/registry.go b/internal/backends/postgresql/metadata/registry.go
index c920a439a9a8..df368761511f 100644
--- a/internal/backends/postgresql/metadata/registry.go
+++ b/internal/backends/postgresql/metadata/registry.go
@@ -73,8 +73,9 @@ var specialCharacters = regexp.MustCompile("[^a-z][^a-z0-9_]*")
 //
 //nolint:vet // for readability
 type Registry struct {
-	p *pool.Pool
-	l *zap.Logger
+	p         *pool.Pool
+	l         *zap.Logger
+	BatchSize int
 
 	// rw protects colls but also acts like a global lock for the whole registry.
 	// The latter effectively replaces transactions (see the postgresql backend package description for more info).
@@ -86,15 +87,16 @@ type Registry struct {
 }
 
 // NewRegistry creates a registry for PostgreSQL databases with a given base URI.
-func NewRegistry(u string, l *zap.Logger, sp *state.Provider) (*Registry, error) {
+func NewRegistry(u string, batchSize int, l *zap.Logger, sp *state.Provider) (*Registry, error) {
 	p, err := pool.New(u, l, sp)
 	if err != nil {
 		return nil, err
 	}
 
 	r := &Registry{
-		p: p,
-		l: l,
+		p:         p,
+		l:         l,
+		BatchSize: batchSize,
 	}
 
 	return r, nil
diff --git a/internal/backends/postgresql/metadata/registry_test.go b/internal/backends/postgresql/metadata/registry_test.go
index ac29e0003042..8c0b25068ec2 100644
--- a/internal/backends/postgresql/metadata/registry_test.go
+++ b/internal/backends/postgresql/metadata/registry_test.go
@@ -91,7 +91,7 @@ func createDatabase(t *testing.T, ctx context.Context) (*Registry, *pgxpool.Pool
 	sp, err := state.NewProvider("")
 	require.NoError(t, err)
 
-	r, err := NewRegistry(u, testutil.Logger(t), sp)
+	r, err := NewRegistry(u, 100, testutil.Logger(t), sp)
 	require.NoError(t, err)
 	t.Cleanup(r.Close)
 
@@ -140,7 +140,7 @@ func TestAuth(t *testing.T) {
 			sp, err := state.NewProvider("")
 			require.NoError(t, err)
 
-			r, err := NewRegistry(tc.uri, testutil.Logger(t), sp)
+			r, err := NewRegistry(tc.uri, 100, testutil.Logger(t), sp)
 			require.NoError(t, err)
 			t.Cleanup(r.Close)
 
diff --git a/internal/backends/sqlite/backend.go b/internal/backends/sqlite/backend.go
index b7678a85b011..44452d7c4429 100644
--- a/internal/backends/sqlite/backend.go
+++ b/internal/backends/sqlite/backend.go
@@ -37,15 +37,16 @@ type backend struct {
 //
 //nolint:vet // for readability
 type NewBackendParams struct {
-	URI string
-	L   *zap.Logger
-	P   *state.Provider
-	_   struct{} // prevent unkeyed literals
+	URI       string
+	L         *zap.Logger
+	P         *state.Provider
+	BatchSize int
+	_         struct{} // prevent unkeyed literals
 }
 
 // NewBackend creates a new Backend.
 func NewBackend(params *NewBackendParams) (backends.Backend, error) {
-	r, err := metadata.NewRegistry(params.URI, params.L, params.P)
+	r, err := metadata.NewRegistry(params.URI, params.BatchSize, params.L, params.P)
 	if err != nil {
 		return nil, err
 	}
diff --git a/internal/backends/sqlite/collection.go b/internal/backends/sqlite/collection.go
index 28c36341086a..6351a93cd22a 100644
--- a/internal/backends/sqlite/collection.go
+++ b/internal/backends/sqlite/collection.go
@@ -109,8 +109,10 @@ func (c *collection) InsertAll(ctx context.Context, params *backends.InsertAllPa
 	meta := c.r.CollectionGet(ctx, c.dbName, c.name)
 
 	err := db.InTransaction(ctx, func(tx *fsql.Tx) error {
-		// TODO https://github.com/FerretDB/FerretDB/issues/3708
-		const batchSize = 100
+		batchSize := c.r.BatchSize
+		if batchSize < 1 {
+			panic("batch-size should be greater or equal to 1")
+		}
 
 		var batch []*types.Document
 		docs := params.Docs
diff --git a/internal/backends/sqlite/collection_test.go b/internal/backends/sqlite/collection_test.go
index f257ffcae0a8..d062064cf51e 100644
--- a/internal/backends/sqlite/collection_test.go
+++ b/internal/backends/sqlite/collection_test.go
@@ -39,7 +39,7 @@ func TestCappedCollectionInsertAllQueryExplain(t *testing.T) {
 	sp, err := state.NewProvider("")
 	require.NoError(t, err)
 
-	b, err := NewBackend(&NewBackendParams{URI: testutil.TestSQLiteURI(t, ""), L: testutil.Logger(t), P: sp})
+	b, err := NewBackend(&NewBackendParams{URI: testutil.TestSQLiteURI(t, ""), L: testutil.Logger(t), P: sp, BatchSize: 100})
 	require.NoError(t, err)
 	t.Cleanup(b.Close)
 
diff --git a/internal/backends/sqlite/database_test.go b/internal/backends/sqlite/database_test.go
index 2d9b0a343271..d287733fee17 100644
--- a/internal/backends/sqlite/database_test.go
+++ b/internal/backends/sqlite/database_test.go
@@ -72,7 +72,7 @@ func TestDatabaseStatsFreeStorage(t *testing.T) {
 		name, params := name, params
 		t.Run(name, func(t *testing.T) {
 			uri := testutil.TestSQLiteURI(t, "") + params
-			b, err := NewBackend(&NewBackendParams{URI: uri, L: testutil.Logger(t), P: sp})
+			b, err := NewBackend(&NewBackendParams{URI: uri, L: testutil.Logger(t), P: sp, BatchSize: 100})
 			require.NoError(t, err)
 
 			t.Cleanup(b.Close)
diff --git a/internal/backends/sqlite/metadata/registry.go b/internal/backends/sqlite/metadata/registry.go
index 23e1e6fe4e75..65d12d641e8c 100644
--- a/internal/backends/sqlite/metadata/registry.go
+++ b/internal/backends/sqlite/metadata/registry.go
@@ -56,8 +56,9 @@ const (
 //
 // Exported methods are safe for concurrent use. Unexported methods are not.
 type Registry struct {
-	p *pool.Pool
-	l *zap.Logger
+	p         *pool.Pool
+	l         *zap.Logger
+	BatchSize int
 
 	// rw protects colls but also acts like a global lock for the whole registry.
 	// The latter effectively replaces transactions (see the sqlite backend package description for more info).
@@ -69,16 +70,17 @@ type Registry struct {
 }
 
 // NewRegistry creates a registry for SQLite databases in the directory specified by SQLite URI.
-func NewRegistry(u string, l *zap.Logger, sp *state.Provider) (*Registry, error) {
+func NewRegistry(u string, batchSize int, l *zap.Logger, sp *state.Provider) (*Registry, error) {
 	p, initDBs, err := pool.New(u, l, sp)
 	if err != nil {
 		return nil, err
 	}
 
 	r := &Registry{
-		p:     p,
-		l:     l,
-		colls: map[string]map[string]*Collection{},
+		p:         p,
+		l:         l,
+		BatchSize: batchSize,
+		colls:     map[string]map[string]*Collection{},
 	}
 
 	for name, db := range initDBs {
diff --git a/internal/backends/sqlite/metadata/registry_test.go b/internal/backends/sqlite/metadata/registry_test.go
index cb3a4ec7074d..64739cfe36c9 100644
--- a/internal/backends/sqlite/metadata/registry_test.go
+++ b/internal/backends/sqlite/metadata/registry_test.go
@@ -75,7 +75,7 @@ func TestCreateDrop(t *testing.T) {
 	sp, err := state.NewProvider("")
 	require.NoError(t, err)
 
-	r, err := NewRegistry(testutil.TestSQLiteURI(t, ""), testutil.Logger(t), sp)
+	r, err := NewRegistry(testutil.TestSQLiteURI(t, ""), 100, testutil.Logger(t), sp)
 	require.NoError(t, err)
 	t.Cleanup(r.Close)
 
@@ -113,7 +113,7 @@ func TestCreateDropStress(t *testing.T) {
 	} {
 		t.Run(testName, func(t *testing.T) {
 			uri := testutil.TestSQLiteURI(t, "") + params
-			r, err := NewRegistry(uri, testutil.Logger(t), sp)
+			r, err := NewRegistry(uri, 100, testutil.Logger(t), sp)
 			require.NoError(t, err)
 			t.Cleanup(r.Close)
 
@@ -158,7 +158,7 @@ func TestCreateSameStress(t *testing.T) {
 	} {
 		t.Run(testName, func(t *testing.T) {
 			uri := testutil.TestSQLiteURI(t, "") + params
-			r, err := NewRegistry(uri, testutil.Logger(t), sp)
+			r, err := NewRegistry(uri, 100, testutil.Logger(t), sp)
 			require.NoError(t, err)
 			t.Cleanup(r.Close)
 
@@ -227,7 +227,7 @@ func TestDropSameStress(t *testing.T) {
 	} {
 		t.Run(testName, func(t *testing.T) {
 			uri := testutil.TestSQLiteURI(t, "") + params
-			r, err := NewRegistry(uri, testutil.Logger(t), sp)
+			r, err := NewRegistry(uri, 100, testutil.Logger(t), sp)
 			require.NoError(t, err)
 			t.Cleanup(r.Close)
 
@@ -280,7 +280,7 @@ func TestCreateDropSameStress(t *testing.T) {
 	} {
 		t.Run(testName, func(t *testing.T) {
 			uri := testutil.TestSQLiteURI(t, "") + params
-			r, err := NewRegistry(uri, testutil.Logger(t), sp)
+			r, err := NewRegistry(uri, 100, testutil.Logger(t), sp)
 			require.NoError(t, err)
 			t.Cleanup(r.Close)
 
@@ -329,7 +329,7 @@ func TestIndexesCreateDrop(t *testing.T) {
 	sp, err := state.NewProvider("")
 	require.NoError(t, err)
 
-	r, err := NewRegistry(testutil.TestSQLiteURI(t, ""), testutil.Logger(t), sp)
+	r, err := NewRegistry(testutil.TestSQLiteURI(t, ""), 100, testutil.Logger(t), sp)
 	require.NoError(t, err)
 	t.Cleanup(r.Close)
 
diff --git a/internal/backends/sqlite/sqlite_test.go b/internal/backends/sqlite/sqlite_test.go
index a5251637cdb9..85c574406e3d 100644
--- a/internal/backends/sqlite/sqlite_test.go
+++ b/internal/backends/sqlite/sqlite_test.go
@@ -31,7 +31,7 @@ func TestCollectionsStats(t *testing.T) {
 	sp, err := state.NewProvider("")
 	require.NoError(t, err)
 
-	r, err := metadata.NewRegistry(testutil.TestSQLiteURI(t, ""), testutil.Logger(t), sp)
+	r, err := metadata.NewRegistry(testutil.TestSQLiteURI(t, ""), 100, testutil.Logger(t), sp)
 	require.NoError(t, err)
 	t.Cleanup(r.Close)
 
diff --git a/internal/handler/handler.go b/internal/handler/handler.go
index 37cd03ea2cb1..511db6b7eb9b 100644
--- a/internal/handler/handler.go
+++ b/internal/handler/handler.go
@@ -81,6 +81,7 @@ type NewOpts struct {
 	CappedCleanupInterval   time.Duration
 	CappedCleanupPercentage uint8
 	EnableNewAuth           bool
+	BatchSize               int
 }
 
 // New returns a new handler.
diff --git a/internal/handler/msg_insert.go b/internal/handler/msg_insert.go
index 7571ce1dc3c7..69c30fcadf4a 100644
--- a/internal/handler/msg_insert.go
+++ b/internal/handler/msg_insert.go
@@ -85,13 +85,10 @@ func (h *Handler) MsgInsert(ctx context.Context, msg *wire.OpMsg) (*wire.OpMsg,
 
 	var done bool
 	for !done {
-		// TODO https://github.com/FerretDB/FerretDB/issues/3708
-		const batchSize = 1000
+		docs := make([]*types.Document, 0, h.BatchSize)
+		docsIndexes := make([]int, 0, h.BatchSize)
 
-		docs := make([]*types.Document, 0, batchSize)
-		docsIndexes := make([]int, 0, batchSize)
-
-		for j := 0; j < batchSize; j++ {
+		for j := 0; j < h.BatchSize; j++ {
 			var i int
 			var d any
 
diff --git a/internal/handler/registry/hana.go b/internal/handler/registry/hana.go
index 24eb8cf190af..0b94f9f67802 100644
--- a/internal/handler/registry/hana.go
+++ b/internal/handler/registry/hana.go
@@ -27,9 +27,10 @@ func init() {
 		opts.Logger.Warn("HANA handler is in alpha. It is not supported yet.")
 
 		b, err := hana.NewBackend(&hana.NewBackendParams{
-			URI: opts.HANAURL,
-			L:   opts.Logger.Named("hana"),
-			P:   opts.StateProvider,
+			URI:       opts.HANAURL,
+			L:         opts.Logger.Named("hana"),
+			P:         opts.StateProvider,
+			BatchSize: opts.BatchSize,
 		})
 		if err != nil {
 			return nil, nil, err
@@ -48,6 +49,7 @@ func init() {
 			CappedCleanupPercentage: opts.CappedCleanupPercentage,
 			CappedCleanupInterval:   opts.CappedCleanupInterval,
 			EnableNewAuth:           opts.EnableNewAuth,
+			BatchSize:               opts.BatchSize,
 		}
 
 		h, err := handler.New(handlerOpts)
diff --git a/internal/handler/registry/mysql.go b/internal/handler/registry/mysql.go
index 11a1f4f803fb..7ac10b6406b6 100644
--- a/internal/handler/registry/mysql.go
+++ b/internal/handler/registry/mysql.go
@@ -45,6 +45,7 @@ func init() {
 			CappedCleanupPercentage: opts.CappedCleanupPercentage,
 			CappedCleanupInterval:   opts.CappedCleanupInterval,
 			EnableNewAuth:           opts.EnableNewAuth,
+			BatchSize:               opts.BatchSize,
 		}
 
 		h, err := handler.New(handlerOpts)
diff --git a/internal/handler/registry/postgresql.go b/internal/handler/registry/postgresql.go
index 36ce440569c4..f24eadd5b130 100644
--- a/internal/handler/registry/postgresql.go
+++ b/internal/handler/registry/postgresql.go
@@ -25,9 +25,10 @@ import (
 func init() {
 	registry["postgresql"] = func(opts *NewHandlerOpts) (*handler.Handler, CloseBackendFunc, error) {
 		b, err := postgresql.NewBackend(&postgresql.NewBackendParams{
-			URI: opts.PostgreSQLURL,
-			L:   opts.Logger.Named("postgresql"),
-			P:   opts.StateProvider,
+			URI:       opts.PostgreSQLURL,
+			L:         opts.Logger.Named("postgresql"),
+			P:         opts.StateProvider,
+			BatchSize: opts.BatchSize,
 		})
 		if err != nil {
 			return nil, nil, err
@@ -47,6 +48,7 @@ func init() {
 			CappedCleanupPercentage: opts.CappedCleanupPercentage,
 			CappedCleanupInterval:   opts.CappedCleanupInterval,
 			EnableNewAuth:           opts.EnableNewAuth,
+			BatchSize:               opts.BatchSize,
 		}
 
 		h, err := handler.New(handlerOpts)
diff --git a/internal/handler/registry/registry.go b/internal/handler/registry/registry.go
index 47c98923c0b3..a3d4d0e89a64 100644
--- a/internal/handler/registry/registry.go
+++ b/internal/handler/registry/registry.go
@@ -71,6 +71,7 @@ type TestOpts struct {
 	CappedCleanupInterval   time.Duration
 	CappedCleanupPercentage uint8
 	EnableNewAuth           bool
+	BatchSize               int
 	_                       struct{} // prevent unkeyed literals
 }
 
diff --git a/internal/handler/registry/sqlite.go b/internal/handler/registry/sqlite.go
index 7c0613256463..efa5c98bc988 100644
--- a/internal/handler/registry/sqlite.go
+++ b/internal/handler/registry/sqlite.go
@@ -25,9 +25,10 @@ import (
 func init() {
 	registry["sqlite"] = func(opts *NewHandlerOpts) (*handler.Handler, CloseBackendFunc, error) {
 		b, err := sqlite.NewBackend(&sqlite.NewBackendParams{
-			URI: opts.SQLiteURL,
-			L:   opts.Logger.Named("sqlite"),
-			P:   opts.StateProvider,
+			URI:       opts.SQLiteURL,
+			L:         opts.Logger.Named("sqlite"),
+			P:         opts.StateProvider,
+			BatchSize: opts.BatchSize,
 		})
 		if err != nil {
 			return nil, nil, err
@@ -47,6 +48,7 @@ func init() {
 			CappedCleanupPercentage: opts.CappedCleanupPercentage,
 			CappedCleanupInterval:   opts.CappedCleanupInterval,
 			EnableNewAuth:           opts.EnableNewAuth,
+			BatchSize:               opts.BatchSize,
 		}
 
 		h, err := handler.New(handlerOpts)
diff --git a/internal/util/fsql/db.go b/internal/util/fsql/db.go
index f550c0306705..2eaa3d75c3da 100644
--- a/internal/util/fsql/db.go
+++ b/internal/util/fsql/db.go
@@ -35,9 +35,10 @@ import (
 type DB struct {
 	*metricsCollector
 
-	sqlDB *sql.DB
-	l     *zap.Logger
-	token *resource.Token
+	sqlDB     *sql.DB
+	l         *zap.Logger
+	token     *resource.Token
+	BatchSize int
 }
 
 // WrapDB creates a new DB.