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mysql_binlog_tutorial
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| # this is a partial code | |
| # skip to 462 | |
| # https://dev.mysql.com/doc/internals/en/query-event.html | |
| file_pointer = 462 | |
| print("==================") | |
| print("file_pointer", file_pointer) | |
| f.seek(file_pointer) | |
| header = Header() | |
| header.unpack(f.read(header_length)) | |
| file_pointer += header_length | |
| print(header) | |
| post_header = f.read(13) | |
| unpacked = struct.unpack('<IIBHH', post_header) | |
| """ | |
| uint32_t thread_id; | |
| uint32_t query_exec_time; | |
| size_t db_len; | |
| uint16_t error_code; | |
| uint16_t status_vars_len; | |
| """ | |
| print(f"thread_id : {unpacked[0]} " | |
| f"query_exec_time: {unpacked[1]} " | |
| f"db_len: {unpacked[2]} " | |
| f"error_code: {unpacked[3]} " | |
| f"status_vars_len: {unpacked[4]} " | |
| f"") | |
| # Q_FLAGS2_CODE | |
| key = f.read(1) | |
| unpacked = struct.unpack('<B', key)[0] | |
| print("Key", unpacked) | |
| value = f.read(4) | |
| unpacked = struct.unpack('<I', value)[0] | |
| print("Q_FLAGS2_CODE", unpacked) | |
| # Q_SQL_MODE_CODE | |
| key = f.read(1) | |
| unpacked = struct.unpack('<B', key)[0] | |
| print("Key", unpacked) | |
| value = f.read(8) | |
| unpacked = struct.unpack('<Q', value)[0] | |
| print("Q_SQL_MODE_CODE", unpacked) | |
| # Q_TIME_ZONE_CODE | |
| key = f.read(1) | |
| unpacked = struct.unpack('<B', key)[0] | |
| print("key", unpacked) | |
| value = f.read(1) | |
| lenx = struct.unpack('<B', value)[0] | |
| timezone = f.read(lenx) | |
| print("Timezone", timezone.decode()) | |
| # Q_CHARSET_CODE | |
| key = f.read(1) | |
| unpacked = struct.unpack('<B', key)[0] | |
| print("key", unpacked) | |
| value = f.read(6) | |
| unpacked = struct.unpack('<HHH', value) | |
| # 2-byte character_set_client + 2-byte collation_connection + 2-byte collation_server | |
| print(f"character_set_client: {unpacked[0]} " | |
| f"collation_connection: {unpacked[1]} " | |
| f"collation_server: {unpacked[2]}") | |
| # Q_UPDATED_DB_NAMES | |
| key = f.read(1) | |
| unpacked = struct.unpack('<B', key)[0] | |
| print("key", unpacked) | |
| lenx = struct.unpack('<B', f.read(1))[0] | |
| # read by byte until find terminate char | |
| for i in range(lenx): | |
| string = b'' | |
| while True: | |
| char = f.read(1) | |
| if char == b'\0': | |
| break | |
| string += char | |
| print("Database", string) | |
| # Get DB Name | |
| database = f.read(11) | |
| print("schema:", database.decode()) | |
| f.read(1) | |
| # Get the query | |
| query = f.read(header.log_pos - f.tell() - 4) | |
| print("query:", query.decode()) | |
| crc32 = struct.unpack("<I", f.read(4))[0] | |
| print("crc32:", hex(crc32)) |
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