Retrieve serial ID with Npgsql when inserting with ExecuteScalar

Question

I\'m trying to insert a row into a PostgreSQL table with a serial primary key and I need to retrieve this column after it was inserted. I got something like this:

Th

Answer 1

In order to select the last identity inserted you need to use: currval(sequencename)

so your select statement should look like:

NpgsqlCommand query = new NpgsqlCommand("insert into pais(nombre, capital) values(@nombre, @capital);select currval('table_sequence');", conn);