Re: TOAST condition for column size

2021-01-20 Thread torikoshia
On 2021-01-19 19:32, Amit Kapila wrote: On Mon, Jan 18, 2021 at 7:53 PM torikoshia Because no benefit is to be expected by compressing it. The size will be mostly the same. Also, even if we somehow try to fit this data via toast, I think reading speed will be slower because for all such columns a

Re: TOAST condition for column size

2021-01-19 Thread Tom Lane
Dilip Kumar writes: > On Tue, 19 Jan 2021 at 6:28 PM, Amit Kapila wrote: >> Won't it be safe because we don't align individual attrs of type >> varchar where length is less than equal to 127? > Yeah right, I just missed that point. Yeah, the minimum on biggest_size has nothing to do with align

Re: TOAST condition for column size

2021-01-19 Thread Dilip Kumar
On Tue, 19 Jan 2021 at 6:28 PM, Amit Kapila wrote: > On Tue, Jan 19, 2021 at 5:18 PM Dilip Kumar wrote: > > > > On Mon, Jan 18, 2021 at 7:53 PM torikoshia > wrote: > > > > > > Hi, > > > > > > When I created a table consisting of 400 VARCHAR columns and tried > > > to INSERT a record which rows

Re: TOAST condition for column size

2021-01-19 Thread Amit Kapila
On Tue, Jan 19, 2021 at 5:18 PM Dilip Kumar wrote: > > On Mon, Jan 18, 2021 at 7:53 PM torikoshia wrote: > > > > Hi, > > > > When I created a table consisting of 400 VARCHAR columns and tried > > to INSERT a record which rows were all the same size, there were > > cases where I got an error due t

Re: TOAST condition for column size

2021-01-19 Thread Dilip Kumar
On Mon, Jan 18, 2021 at 7:53 PM torikoshia wrote: > > Hi, > > When I created a table consisting of 400 VARCHAR columns and tried > to INSERT a record which rows were all the same size, there were > cases where I got an error due to exceeding the size limit per > row. > >=# -- create a table co

Re: TOAST condition for column size

2021-01-19 Thread Amit Kapila
On Mon, Jan 18, 2021 at 7:53 PM torikoshia wrote: > > Hi, > I confirmed these sizes in my environment but AFAIU they would be > the same size in any environment. > > So, as a result of adjusting the alignment, 20~23 bytes seems to > fail. > > I wonder if it might be better not to adjust the align

TOAST condition for column size

2021-01-18 Thread torikoshia
Hi, When I created a table consisting of 400 VARCHAR columns and tried to INSERT a record which rows were all the same size, there were cases where I got an error due to exceeding the size limit per row. =# -- create a table consisting of 400 VARCHAR columns =# CREATE TABLE t1 (c1 VARCHAR(10