MEHUL.JAIN
I have a use case where I want to insert large number of rows in PG Table at once from Ecto. But ecto has a param limit of 65_535, so the max rows I can insert is 65_535 / tot_number_of_fields_in_schema.
To overcome this, I am trying to see if I can to
Repo.insert_all(Schema, query)
query = from(c in Ecto.Query.fragment("SELECT * FROM unnest(? as field1, ? as field2"), ^field1_array, ^field2_array)
The idea here is, the total params will be 2 in this case
-- before
INSERT INTO users
(id, name)
VALUES ($1,$2),($3,$4);
-- after
INSERT INTO users
(id, name)
(select * from unnest($1::int[], $2::int[]));
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LostKobrakai
Take a look at:
Though I also found jsonb_to_recordset quite useful:
MEHUL.JAIN
I think using Fragment directly for inserts does not work, what you have done with join will work in case of updates
MEHUL.JAIN
I have done this:
But how do I remove prefix from cte query? I have a multi tenant/schema application, so I need prefix when I would try to do
DBWrapper.insert_all(SchemaModule, query)