Re: Insert with Jsonb column hangs

On 3/9/24 08:00, kuldeep singh wrote:
> Copy may not work in our scenario since we need to join data from
> multiple tables & then  convert it to json using  row_to_json . This
> json data eventually  needs to be stored in a target table .

Per:

https://www.postgresql.org/docs/current/sql-copy.html

"
COPY { table_name [ ( column_name [, ...] ) ] | ( query ) }

<...>

query

A SELECT, VALUES, INSERT, UPDATE, or DELETE command whose results
are to be copied. Note that parentheses are required around the query.

For INSERT, UPDATE and DELETE queries a RETURNING clause must be
provided, and the target relation must not have a conditional rule, nor
an ALSO rule, nor an INSTEAD rule that expands to multiple statements.
"

>
> Will it be better if we break the process into batches of like 10,000
> rows & insert the data in its individual transactions? Or any other
> better solution available ?
>
> On Sat, Mar 9, 2024 at 9:01 PM hector vass <hector(dot)vass(at)gmail(dot)com
> <mailto:hector(dot)vass(at)gmail(dot)com>> wrote:
>
>
>
> On Sat, Mar 9, 2024 at 3:02 PM kuldeep singh
> <kuldeeparora89(at)gmail(dot)com <mailto:kuldeeparora89(at)gmail(dot)com>> wrote:
>
> Hi,
>
> We are inserting data close to 1M record & having a single Jsonb
> column but query is getting stuck.
>
> We are using insert into select * .. , so all the operations are
> within the DB.
>
> If we are running select query individually then it is returning
> the data in 40 sec for all rows but with insert it is getting stuck.
>
> PG Version - 15.
>
> What could be the problem here ?
>
> Regards,
> KD
>
>
> insert 1M rows especially JSON that can be large, variable in size
> and stored as blobs and indexed is not perhaps the correct way to do
> this
> insert performance will also depend on your tuning.  Supporting
> transactions, users or bulk processing are 3x sides of a compromise.
> you should perhaps consider that insert is for inserting a few rows
> into live tables ... you might be better using copy or \copy,
> pg_dump if you are just trying to replicate a large table
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com