On Sat, Mar 9, 2024 at 4:10 PM Adrian Klaver <adrian.kla...@aklaver.com> wrote:
> 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.v...@gmail.com > > <mailto:hector.v...@gmail.com>> wrote: > > > > > > > > On Sat, Mar 9, 2024 at 3:02 PM kuldeep singh > > <kuldeeparor...@gmail.com <mailto:kuldeeparor...@gmail.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.kla...@aklaver.com What Adrian Klaver said ^ discovered even this works... create view myview as (select row_to_json from mytable); create table newtable as select * from myview where 1=0; copy myview to program 'psql mydb postgres -c ''copy newtable from stdin'' ' ;
