diff --git a/src/app/services/updaters/fl_updater.py b/src/app/services/updaters/fl_updater.py
index b8e942f..4315bff 100644
--- a/src/app/services/updaters/fl_updater.py
+++ b/src/app/services/updaters/fl_updater.py
@@ -1,5 +1,4 @@
 import asyncio
-import platform
 from typing import Optional
 
 from aiologger import Logger
@@ -54,40 +53,15 @@ class FlUpdater(BaseUpdater):
     sequences_updated_event: asyncio.Event
     genres_updated_event: asyncio.Event
 
-    platform: str
     logger: Logger
 
-    async def log(self, message):
-        if "windows" in self.platform.lower():
-            print(message)
-        else:
-            await self.logger.info(message)
-
-    async def _drop_tables(self):
-        async with self.mysql_pool.acquire() as conn:
-            async with conn.cursor() as cursor:
-                cursor.execute(
-                    "DROP TABLE IF EXISTS libaannotations;"
-                    "DROP TABLE IF EXISTS libapics;"
-                    "DROP TABLE IF EXISTS libavtor;"
-                    "DROP TABLE IF EXISTS libavtorname;"
-                    "DROP TABLE IF EXISTS libbannotations;"
-                    "DROP TABLE IF EXISTS libbook;"
-                    "DROP TABLE IF EXISTS libbpics;"
-                    "DROP TABLE IF EXISTS libgenre;"
-                    "DROP TABLE IF EXISTS libgenrelist;"
-                    "DROP TABLE IF EXISTS libseq;"
-                    "DROP TABLE IF EXISTS libseqname;"
-                    "DROP TABLE IF EXISTS libtranslator;"
-                )
-
     async def _import_dump(self, filename: str):
-        result = await run(
+        await run(
             f"wget -O - {env_config.FL_BASE_URL}/sql/{filename}.gz | gunzip | "
             f"mysql -h {env_config.MYSQL_HOST} -u {env_config.MYSQL_USER} "
             f'-p"{env_config.MYSQL_PASSWORD}" {env_config.MYSQL_DB_NAME}'
         )
-        await self.log(f"Imported {filename}: {result}.")
+        await self.logger.info(f"Imported {filename}")
 
     async def _prepare(self):
         posgres_pool = await asyncpg.create_pool(
@@ -112,7 +86,7 @@ class FlUpdater(BaseUpdater):
         self.postgres_pool = posgres_pool
 
     async def _set_source(self):
-        await self.log("Set source...")
+        await self.logger.info("Set source...")
 
         source_row = await self.postgres_pool.fetchrow(
             "SELECT id FROM sources WHERE name = 'flibusta';"
@@ -129,7 +103,7 @@ class FlUpdater(BaseUpdater):
 
         self.SOURCE = source_row["id"]
 
-        await self.log("Source has set!")
+        await self.logger.info("Source has set!")
 
     async def _update_authors(self):
         def prepare_author(row: list):
@@ -141,26 +115,50 @@ class FlUpdater(BaseUpdater):
                 remove_wrong_ch(row[3]),
             ]
 
-        await self.log("Update authors...")
+        await self.logger.info("Update authors...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_author(
+                source_ smallint, remote_id_ int, first_name_ varchar, last_name_ varchar, middle_name_ varchar
+            ) RETURNS void AS $$
+                BEGIN
+                    IF EXISTS (SELECT * FROM authors WHERE source = source_ AND remote_id = remote_id_) THEN
+                        UPDATE authors SET first_name = first_name_, last_name = last_name_, middle_name = middle_name_
+                        WHERE source = source_ AND remote_id = remote_id_;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO authors (source, remote_id, first_name, last_name, middle_name)
+                        VALUES (source_, remote_id_, first_name_, last_name_, middle_name_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute(
-                    "SELECT AvtorId, FirstName, LastName, MiddleName FROM libavtorname;"
-                )
+                await cursor.execute("SELECT COUNT(*) FROM libavtorname;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT AvtorId, FirstName, LastName, MiddleName FROM libavtorname LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO authors (source, remote_id, first_name, last_name, middle_name) "
-                        "VALUES ($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar)) "
-                        "ON CONFLICT (source, remote_id) "
-                        "DO UPDATE SET first_name = EXCLUDED.first_name, last_name = EXCLUDED.last_name, middle_name = EXCLUDED.middle_name;",
+                        "SELECT update_author($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar));",
                         [prepare_author(row) for row in rows],
                     )
 
         self.authors_updated_event.set()
 
-        await self.log("Authors updated!")
+        await self.logger.info("Authors updated!")
 
     async def _update_books(self):
         replace_dict = {"ru-": "ru", "ru~": "ru"}
@@ -181,76 +179,153 @@ class FlUpdater(BaseUpdater):
                 row[5] == "1",
             ]
 
-        await self.log("Update books...")
+        await self.logger.info("Update books...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_book(
+                source_ smallint, remote_id_ int, title_ varchar, lang_ varchar,
+                file_type_ varchar, uploaded_ date, is_deleted_ boolean
+            ) RETURNS void AS $$
+                BEGIN
+                    IF EXISTS (SELECT * FROM books WHERE source = source_ AND remote_id = remote_id_) THEN
+                        UPDATE books SET title = title_, lang = lang_, file_type = file_type_,
+                                         uploaded = uploaded_, is_deleted = is_deleted
+                        WHERE source = source_ AND remote_id = remote_id_;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO books (source, remote_id, title, lang, file_type, uploaded, is_deleted)
+                        VALUES (source_, remote_id_, title_, lang_, file_type_, uploaded_, is_deleted_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute(
-                    "SELECT BookId, Title, Lang, FileType, Time, Deleted FROM libbook;"
-                )
+                await cursor.execute("SELECT COUNT(*) FROM libbook;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, Title, Lang, FileType, Time, Deleted FROM libbook LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO books (source, remote_id, title, lang, file_type, uploaded, is_deleted) "
-                        "VALUES ($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar), $6, $7) "
-                        "ON CONFLICT (source, remote_id) "
-                        "DO UPDATE SET title = EXCLUDED.title, lang = EXCLUDED.lang, file_type = EXCLUDED.file_type, "
-                        "uploaded = EXCLUDED.uploaded, is_deleted = EXCLUDED.is_deleted;",
+                        "SELECT update_book($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar), $6, $7);",
                         [prepare_book(row) for row in rows],
                     )
 
         self.books_updated_event.set()
 
-        await self.log("Books updated!")
+        await self.logger.info("Books updated!")
 
     async def _update_books_authors(self):
         await self.books_updated_event.wait()
         await self.authors_updated_event.wait()
 
-        await self.log("Update books_authors...")
+        await self.logger.info("Update books_authors...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_book_author(source_ smallint, book_ integer, author_ integer) RETURNS void AS $$
+                DECLARE
+                    book_id integer := -1;
+                    author_id integer := -1;
+                BEGIN
+                    SELECT id INTO book_id FROM books WHERE source = source_ AND remote_id = book_;
+                    SELECT id INTO author_id FROM authors WHERE source = source_ AND remote_id = author_;
+
+                    IF EXISTS (SELECT * FROM book_authors WHERE book = book_id AND author = author_id) THEN
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO book_authors (book, author) VALUES (book_id, author_id);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute("SELECT BookId, AvtorId FROM libavtor;")
+                await cursor.execute("SELECT COUNT(*) FROM libavtorname;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, AvtorId FROM libavtor LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO book_authors (book, author) "
-                        "SELECT "
-                        "(SELECT id FROM books WHERE source = $1 AND remote_id = $2), "
-                        "(SELECT id FROM authors WHERE source = $1 AND remote_id = $3) "
-                        "ON CONFLICT (book, author) DO NOTHING;",
+                        "SELECT update_book_author($1, $2, $3);",
                         [(self.SOURCE, *row) for row in rows],
                     )
 
-        await self.log("Books_authors updated!")
+        await self.logger.info("Books_authors updated!")
 
     async def _update_translations(self):
         await self.books_updated_event.wait()
         await self.authors_updated_event.wait()
 
-        await self.log("Update translations...")
+        await self.logger.info("Update translations...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_translation(source_ smallint, book_ integer, author_ integer, position_ smallint) RETURNS void AS $$
+                DECLARE
+                    book_id integer := -1;
+                    author_id integer := -1;
+                BEGIN
+                    SELECT id INTO book_id FROM books WHERE source = source_ AND remote_id = book_;
+                    SELECT id INTO author_id FROM authors WHERE source = source_ AND remote_id = author_;
+
+                    IF EXISTS (SELECT * FROM translations WHERE book = book_id AND author = author_id) THEN
+                        UPDATE translations SET position = position_
+                        WHERE book = book_id AND author = author_id;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO translations (book, author, position) VALUES (book_id, author_id, position_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
                 await cursor.execute(
-                    "SELECT BookId, TranslatorId, Pos FROM libtranslator "
+                    "SELECT COUNT(*) FROM libtranslator "
                     "WHERE BookId IN (SELECT BookId FROM libbook);"
                 )
 
-                while rows := await cursor.fetchmany(32):
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, TranslatorId, Pos FROM libtranslator "
+                        "WHERE BookId IN (SELECT BookId FROM libbook) "
+                        "LIMIT 4096 OFFSET {offset};".format(offset=offset)
+                    )
+
+                    rows = await cursor.fetchall()
+
                     await self.postgres_pool.executemany(
-                        "INSERT INTO translations (book, author, position) "
-                        "SELECT "
-                        "(SELECT id FROM books WHERE source = $1 AND remote_id = $2), "
-                        "(SELECT id FROM authors WHERE source = $1 AND remote_id = $3), "
-                        "$4 "
-                        "ON CONFLICT (book, author) "
-                        "DO UPDATE SET position = EXCLUDED.position;",
+                        "SELECT update_translation($1, $2, $3, $4)",
                         [(self.SOURCE, *row) for row in rows],
                     )
 
-        await self.log("Translations updated!")
+        await self.logger.info("Translations updated!")
 
     async def _update_sequences(self):
         def prepare_sequence(row: list):
@@ -260,89 +335,172 @@ class FlUpdater(BaseUpdater):
                 remove_wrong_ch(row[1]),
             ]
 
-        await self.log("Update sequences...")
+        await self.logger.info("Update sequences...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_sequences(source_ smallint, remote_id_ int, name_ varchar) RETURNS void AS $$
+                BEGIN
+                    IF EXISTS (SELECT * FROM sequences WHERE source = source_ AND remote_id = remote_id_) THEN
+                        UPDATE sequences SET name = name_ WHERE source = source_ AND remote_id = remote_id_;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO sequences (source, remote_id, name) VALUES (source_, remote_id_, name_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute("SELECT SeqId, SeqName FROM libseqname;")
+                await cursor.execute("SELECT COUNT(*) FROM libseqname;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT SeqId, SeqName FROM libseqname LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO sequences (source, remote_id, name) "
-                        "VALUES ($1, $2, cast($3 as varchar)) "
-                        "ON CONFLICT (source, remote_id) "
-                        "DO UPDATE SET name = EXCLUDED.name;",
+                        "SELECT update_sequences($1, $2, cast($3 as varchar));",
                         [prepare_sequence(row) for row in rows],
                     )
 
         self.sequences_updated_event.set()
 
-        await self.log("Sequences updated!")
+        await self.logger.info("Sequences updated!")
 
     async def _update_sequences_info(self):
         await self.sequences_updated_event.wait()
         await self.books_updated_event.wait()
 
-        await self.log("Update book_sequences...")
+        await self.logger.info("Update book_sequences...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_book_sequence(source_ smallint, book_ integer, sequence_ integer, position_ smallint) RETURNS void AS $$
+                DECLARE
+                    book_id integer := -1;
+                    sequence_id integer := -1;
+                BEGIN
+                    SELECT id INTO book_id FROM books WHERE source = source_ AND remote_id = book_;
+                    SELECT id INTO sequence_id FROM sequences WHERE source = source_ AND remote_id = sequence_;
+
+                    IF EXISTS (SELECT * FROM book_sequences WHERE book = book_id AND sequence = sequence_id) THEN
+                        UPDATE book_sequences SET position = position_ WHERE book = book_id AND sequence = sequence_id;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO book_sequences (book, sequence, position) VALUES (book_id, sequence_id, position_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
                 await cursor.execute(
-                    "SELECT BookId, SeqId, level FROM libseq "
+                    "SELECT COUNT(*) FROM libseq "
                     "WHERE "
                     "BookId IN (SELECT BookId FROM libbook) AND "
                     "SeqId IN (SELECT SeqId FROM libseqname);"
                 )
 
-                while rows := await cursor.fetchmany(32):
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, SeqId, level FROM libseq "
+                        "WHERE "
+                        "BookId IN (SELECT BookId FROM libbook) AND "
+                        "SeqId IN (SELECT SeqId FROM libseqname) "
+                        "LIMIT 4096 OFFSET {offset};".format(offset=offset)
+                    )
+
+                    rows = await cursor.fetchall()
+
                     await self.postgres_pool.executemany(
-                        "INSERT INTO book_sequences (book, sequence, position) "
-                        "SELECT "
-                        "(SELECT id FROM books WHERE source = $1 AND remote_id = $2), "
-                        "(SELECT id FROM sequences WHERE source = $1 AND remote_id = $3), "
-                        "$4 "
-                        "ON CONFLICT (book, sequence) "
-                        "DO UPDATE SET position = EXCLUDED.position;",
+                        "SELECT update_book_sequence($1, $2, $3, $4);",
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Book_sequences updated!")
+        await self.logger.info("Book_sequences updated!")
 
     async def _update_book_annotations(self):
         await self.books_updated_event.wait()
 
-        await self.log("Update book_annotations...")
+        await self.logger.info("Update book_annotations...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_book_annotation(source_ smallint, book_ integer, title_ varchar, text_ text) RETURNS void AS $$
+                DECLARE
+                    book_id integer := -1;
+                BEGIN
+                    SELECT id INTO book_id FROM books WHERE source = source_ AND remote_id = book_;
+
+                    IF EXISTS (SELECT * FROM book_annotations WHERE book = book_id) THEN
+                        UPDATE book_annotations SET title = title_, text = text_ WHERE book = book_id;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO book_annotations (book, title, text) VALUES (book_id, title_, text_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
                 await cursor.execute(
-                    "SELECT BookId, Title, Body FROM libbannotations "
+                    "SELECT COUNT(*) FROM libbannotations "
                     "WHERE BookId IN (SELECT BookId FROM libbook);"
                 )
 
-                while rows := await cursor.fetchmany(32):
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, Title, Body FROM libbannotations "
+                        "WHERE BookId IN (SELECT BookId FROM libbook) "
+                        "LIMIT 4096 OFFSET {offset};".format(offset=offset)
+                    )
+
+                    rows = await cursor.fetchall()
+
                     await self.postgres_pool.executemany(
-                        "INSERT INTO book_annotations (book, title, text) "
-                        "SELECT "
-                        "(SELECT id FROM books WHERE source = $1 AND remote_id = $2), "
-                        "$3, $4 "
-                        "ON CONFLICT (book) "
-                        "DO UPDATE SET title = EXCLUDED.title, text = EXCLUDED.text;",
+                        "SELECT update_book_annotation($1, $2, cast($3 as varchar), cast($4 as text));",
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Book_annotations updated!")
+        await self.logger.info("Book_annotations updated!")
 
         await self._update_book_annotations_pic()
 
     async def _update_book_annotations_pic(self):
-        await self.log("Update book_annotations_pic...")
+        await self.logger.info("Update book_annotations_pic...")
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute("SELECT BookId, File FROM libbpics;")
+                await cursor.execute("SELECT COUNT(*) FROM libbpics;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, File FROM libbpics LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
                         "UPDATE book_annotations "
                         "SET file = cast($3 as varchar) "
@@ -351,42 +509,74 @@ class FlUpdater(BaseUpdater):
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Book_annotation_pics updated!")
+        await self.logger.info("Book_annotation_pics updated!")
 
     async def _update_author_annotations(self):
         await self.authors_updated_event.wait()
 
-        await self.log("Update author_annotations...")
+        await self.logger.info("Update author_annotations...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_author_annotation(source_ smallint, author_ integer, title_ varchar, text_ text) RETURNS void AS $$
+                DECLARE
+                    author_id integer := -1;
+                BEGIN
+                    SELECT id INTO author_id FROM authors WHERE source = source_ AND remote_id = author_;
+
+                    IF EXISTS (SELECT * FROM author_annotations WHERE author = author_id) THEN
+                        UPDATE author_annotations SET title = title_, text = text_ WHERE author = author_id;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO author_annotations (author, title, text) VALUES (author_id, title_, text_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute(
-                    "SELECT AvtorId, Title, Body FROM libaannotations;"
-                )
+                await cursor.execute("SELECT COUNT(*) FROM libaannotations;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT AvtorId, Title, Body FROM libaannotations LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO author_annotations (author, title, text) "
-                        "SELECT "
-                        "(SELECT id FROM authors WHERE source = $1 AND remote_id = $2), "
-                        "$3, $4 "
-                        "ON CONFLICT (author) "
-                        "DO UPDATE SET title = EXCLUDED.title, text = EXCLUDED.text;",
+                        "SELECT update_author_annotation($1, $2, cast($3 as varchar), cast($4 as text));",
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Author_annotation_updated!")
+        await self.logger.info("Author_annotation_updated!")
 
         await self._update_author_annotations_pics()
 
     async def _update_author_annotations_pics(self):
-        await self.log("Update author_annotations_pic...")
+        await self.logger.info("Update author_annotations_pic...")
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute("SELECT AvtorId, File FROM libapics;")
+                await cursor.execute("SELECT COUNT(*) FROM libapics;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT AvtorId, File FROM libapics LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
                         "UPDATE author_annotations "
                         "SET file = cast($3 as varchar) "
@@ -395,58 +585,104 @@ class FlUpdater(BaseUpdater):
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Author_annotatioins_pic updated!")
+        await self.logger.info("Author_annotatioins_pic updated!")
 
     async def _update_genres(self):
-        await self.log("Update genres...")
+        await self.logger.info("Update genres...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_genre(
+                source_ smallint, remote_id_ int, code_ varchar, description_ varchar, meta_ varchar
+            ) RETURNS void AS $$
+                BEGIN
+                    IF EXISTS (SELECT * FROM genres WHERE source = source_ AND remote_id = remote_id_) THEN
+                        UPDATE genres SET code = code_, description = description_, meta = meta_
+                        WHERE source = source_ AND remote_id = remote_id_;
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO authors (source, remote_id, code, description, meta)
+                        VALUES (source_, remote_id_, code_, description_, meta_);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute(
-                    "SELECT GenreId, GenreCode, GenreDesc, GenreMeta FROM libgenrelist;"
-                )
+                await cursor.execute("SELECT COUNT(*) FROM libgenrelist;")
 
-                while rows := await cursor.fetchmany(32):
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT GenreId, GenreCode, GenreDesc, GenreMeta FROM libgenrelist LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
                     await self.postgres_pool.executemany(
-                        "INSERT INTO genres (source, remote_id, code, description, meta) "
-                        "VALUES ($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar)) "
-                        "ON CONFLICT (source, remote_id) "
-                        "DO UPDATE SET code = EXCLUDED.code, description = EXCLUDED.description, meta = EXCLUDED.meta;",
+                        "SELECT update_genre($1, $2, cast($3 as varchar), cast($4 as varchar), cast($5 as varchar));",
                         [[self.SOURCE, *row] for row in rows],
                     )
 
-        await self.log("Genres updated!")
+        await self.logger.info("Genres updated!")
 
     async def _update_books_genres(self):
         await self.books_updated_event.wait()
         await self.genres_updated_event.wait()
 
-        await self.log("Update book_genres...")
+        await self.logger.info("Update book_genres...")
+
+        await self.postgres_pool.execute(
+            """
+            CREATE OR REPLACE FUNCTION update_book_sequence(source_ smallint, book_ integer, genre_ integer) RETURNS void AS $$
+                DECLARE
+                    book_id integer := -1;
+                    genre_id integer := -1;
+                BEGIN
+                    SELECT id INTO book_id FROM books WHERE source = source_ AND remote_id = book_;
+                    SELECT id INTO genre_id FROM genres WHERE source = source_ AND remote_id = genre_;
+
+                    IF EXISTS (SELECT * FROM book_genres WHERE book = book_id AND genre = genre_id) THEN
+                        RETURN;
+                    END IF;
+
+                    INSERT INTO book_genres (book, genre) VALUES (book_id, genre_id);
+                END;
+            $$ LANGUAGE plpgsql;
+        """
+        )
 
         async with self.mysql_pool.acquire() as conn:
             async with conn.cursor() as cursor:
-                await cursor.execute("SELECT BookId, GenreId FROM libgenre;")
+                await cursor.execute("SELECT COUNT(*) FROM libgenre;")
+
+                (rows_count,) = await cursor.fetchone()
+
+                for offset in range(0, rows_count, 4096):
+                    await cursor.execute(
+                        "SELECT BookId, GenreId FROM libgenre LIMIT 4096 OFFSET {offset};".format(
+                            offset=offset
+                        )
+                    )
+
+                    rows = await cursor.fetchall()
 
-                while rows := await cursor.fetchmany(32):
                     await self.postgres_pool.executemany(
-                        "INSERT INTO book_genres (book, genre) "
-                        "SELECT "
-                        "(SELECT id FROM books WHERE source = $1 AND remote_id = $2), "
-                        "(SELECT id FROM genres WHERE source = $1 AND remote_id = $3) "
-                        "ON CONFLICT (book, author) DO NOTHING;",
+                        "SELECT update_book_sequence($1, $2, $3);",
                         [(self.SOURCE, *row) for row in rows],
                     )
 
-        await self.log("Book_genres updated!")
+        await self.logger.info("Book_genres updated!")
 
     async def _update(self) -> bool:
-        self.platform = platform.platform()
         self.logger = Logger.with_default_handlers()
 
         await self._prepare()
 
-        await self._drop_tables()
-
         await asyncio.gather(*[self._import_dump(filename) for filename in self.FILES])
 
         await self._set_source()
diff --git a/src/app/services/webhook.py b/src/app/services/webhook.py
index 22149ac..1ef53d6 100644
--- a/src/app/services/webhook.py
+++ b/src/app/services/webhook.py
@@ -6,6 +6,8 @@ from core.config import env_config, WebhookConfig
 class WebhookSender:
     @classmethod
     async def _make_request(cls, webhook: WebhookConfig):
+        print(f"Make request to {webhook.url}")
+
         async with httpx.AsyncClient() as client:
             request_maker = getattr(client, webhook.method)
             await request_maker(webhook.url, headers=webhook.headers)
diff --git a/src/app/views.py b/src/app/views.py
index 555d65d..484b8a1 100644
--- a/src/app/views.py
+++ b/src/app/views.py
@@ -13,4 +13,4 @@ async def update(updater: UpdaterTypes, background_tasks: BackgroundTasks):
 
     background_tasks.add_task(updater_.update)
 
-    return True
+    return "Ok!"