using cat at input file

Question

I have a file created with mysqldump that is 11GB. I need to use the "mysql" command to import it into a database, but I need to add:

USE db1;

at the top. It would take forever to rewrite the file. Is there a way I can concatenate another file at the beginning of the input redirect to fool it into looking at it as a single file?

text.txt contents:

USE db1;

sql_out.sql contents:

data from mysqldump using the --skip-add-drop-table and --no-create-info options

command attempted:

mysql --host=<host> --user=<user> --password=<pwd> < echo $(cat text.txt sql_out.sql)

When I do that I get:

echo: No such file or directory

If I try it without the echo, I get:

$(cat text.txt sql_out.sql): ambiguous redirect

Is there a way to do this?

Answer 1

You can pipe it in:

cat text.txt sql_out.sql | mysql --host=...

Alternatively, to avoid having to create a new file:

(echo "USE db1;"; cat sql_out.sql) | mysql --host=...

Answer 2

You could use process substitution here:

mysql --host=<host> --user=<user> --password=<pwd> < <(cat text.txt sql_out.sql)

the syntax <(...) treats a process's like a file