Conversion of max_rows_per_page to exp_row_size

If a max_rows_per_page value is set for an allpages-locked table, the value is used to compute an expected row size during the alter table...lock command. The formula is shown in Table 14-7.

Table 14-7: Conversion of max_rows_per_page to exp_row_size

Value of max_rows_per_page

Value of exp_row_size


Percentage value set by default exp_row_size percent


The smaller of:

  • Maximum row size

  • 2002/max_rows_per_page value

For example, if max_rows_per_page is set to 10 for an allpages-locked table with a maximum defined row size of 300 bytes, the exp_row_size value will be 200 (2002/10) after the table is altered to use data-only locking.

If max_rows_per_page is set to 10, but the maximum defined row size is only 150, the expected row size value will be set to 150.