Re: Why the lp_len is 28 not 32?

On 2/26/23 15:35, jacktby@gmail.com wrote:
> use these sqls below:
> create table t(a int);
> insert into t values(1);
> select lp,lp_off,lp_len,t_data from heap_page_items(get_raw_page('t',0));
>  lp | lp_off | lp_len |   t_data   
> ----+--------+--------+------------
>   1 |   8160 |     28 | \x01000000
> --------------------------------------------------------------------------------

Pretty sure this is because we align the data to MAXALIGN, and on x86_64
that's 8 bytes. 28 is not a multiple of 8 while 32 is.

regards

-- 
Tomas Vondra
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