oracle - What does the following expression do <<EOF>tmp -

a shell script database connection using sqlplus contains line:

sqlplus username/password@dbname<<eof>tmp. (here there select sql query) 

i know <<eof indicates start of command. have below doubts in >tmp part.

1)does indicate storing file?

2) if yes put results of sql query alone tmp file or query , results both.

could please clear me on one?

<<eof known "heredocs". means next line in script, line says "eof", read in shell, , offered command on standard input.

in case, sqlplus command being fed sql query if came standard input. then, output of sqlplus being saved file called tmp.

the input , output separate. however, sqlplus command has habit of repeating input output, unless instructed otherwise set echo off.