On 10/26/21 1:04 AM, Arun Suresh wrote:
Dear PG experts,
We have a tenant discriminator column in our tables to enable storage of
data from multiple
tenants. This column is also part of the composite primary key.
The customers may request creation of a tenant copy, which means if they
currently have a
tenant id "ABCD", they would like to copy all data "where tenant_id =
'ABCD'" to a new copy tenant "XYZ".
The copy must also be done on the same table.
Current approach taken is to build a query like below:
INSERT INTO mytable (col1, col2, col3, col4) SELECT col1, 'XYZ', col3,
col4 FROM mytable WHERE col2 = 'ABCD'
Is there a better way to do this?
There could be other tables with foreign key reference, would a simple
ordering of the copy based on table relationship suffice?
That would be my first thought. Of course, FK dependencies quickly become a
rat's nest, so beware.
Also if the table has millions of records, what are the things to take
care of?
Take care of?
Anyway, for millions of rows, I might use COPY instead of INSERT (depending
on how many millions, how many indices, how large the rows, how fast the
machine, etc.
--
Angular momentum makes the world go 'round.
