def checksum_by_chunk()

in core/lib/payload/copy.py [0:0]

• 44 lines of code
• 4 McCabe index (conditional complexity)

    def checksum_by_chunk(self, table_name, dump_after_checksum=False):
        """
        Running checksum for all the existing data in new table. This is to
        make sure there's no data corruption after load and first round of
        replay
        """
        checksum_result = []
        # Checksum by chunk. This is pretty much the same logic as we've used
        # in select_table_into_outfile
        affected_rows = 1
        use_where = False
        outfile_id = 0
        if table_name == self.new_table_name:
            idx_for_checksum = self.find_coverage_index()
            outfile_prefix = "{}.new".format(self.outfile)
        else:
            idx_for_checksum = self._idx_name_for_filter
            outfile_prefix = "{}.old".format(self.outfile)
        while affected_rows:
            checksum = self.query(
                sql.checksum_by_chunk(
                    table_name,
                    self.checksum_column_list,
                    self._pk_for_filter,
                    self.range_start_vars_array,
                    self.range_end_vars_array,
                    self.select_chunk_size,
                    use_where,
                    idx_for_checksum,
                )
            )
            # Dump the data onto local disk for further investigation
            # This will be very helpful when there's a reproducable checksum
            # mismatch issue
            if dump_after_checksum:
                self.execute_sql(
                    sql.dump_current_chunk(
                        table_name,
                        self.checksum_column_list,
                        self._pk_for_filter,
                        self.range_start_vars_array,
                        self.select_chunk_size,
                        idx_for_checksum,
                        use_where,
                    ),
                    ("{}.{}".format(outfile_prefix, str(outfile_id)),),
                )
                outfile_id += 1

            # Refresh where condition range for next select
            if checksum:
                self.refresh_range_start()
                affected_rows = checksum[0]["cnt"]
                checksum_result.append(checksum[0])
                use_where = True
        return checksum_result