将“tail -f”输出重定向到 COPY 命令

Question

I'm trying to redirect the output of the tail -f -n 1 to the Postgres COPY command, the requirement is to execute the COPY command for every output of the tail command.

Came out with the following:

    tail -f -n 1 <source_file> | xargs -n 1 psql -c 'copy <table_name> from stdin'

but this is not working as the output of the tail command is used as a parameter for the psql command rather than as stdin.

Also the more generic:

    tail -f -n 1 <source_file> | psql -tc "copy <table_name> from stdin" 

is not working as the COPY command perform a commit at the end of the stream and not for every single row.

Answer 1

意识到问题在于 COPY 不打算接受流，并且仅当 COPY 命令结束（程序数据结束）时数据才可用，在这种特定情况下，程序从未终止，因为它旨在作为消费者工作。