ruby raised another command is already in progress-CodePudding

I would like to enter a large amount of data in my file. To do this, I am thinking of using postgresql's asynchronous processing to do the query. The code is as follows.

raw_conn = ActiveRecord::Base.connection.raw_connection

raw_conn.send_query("SELECT id FROM users")
raw_conn.set_single_row_mode
begin
  raw_conn.get_result.stream_each do |f|
    # writing process to file
  end
end

raw_conn.send_query("SELECT id FROM logins")
raw_conn.set_single_row_mode
begin
  raw_conn.get_result.stream_each do |f|
    # writing process to file
  end
end

When the second send_query is executed, the following error occurs.

 another command is already in progress

I had a feeling that the connection pool was the cause, but the documentation did not mention it. Is there any way to run send_query more than once and get results?

CodePudding user response：

I Resolved. I tried to reset the connection before sending a new query, and it worked.

begin
  raw_conn.get_result.stream_each do |f|
    # writing process to file
  end
ensure
 raw_conn.reset
end