php - line 40: syntax error near unexpected token | Import database from URL

one text

script Directadmin: domain_create_post.sh

#2 DOWNLOAD WORDPRESS FROM URL
    cd /home/$username/domains/$domain/public_html/
    wget https://mywebsite.com/templ/template.zip
    unzip template.zip

   #3 DOWNLOAD AND INSERT TABLE TO CREATED DATABASE
exec('mysql -u '.DB_USER.' -p'.DB_PASSWORD.' '.DB_NAME.' table_name < mydomain.com/files/database.sql;');

#2 working correct. I get issue with #3.

Error log file:

    line 40: syntax error near unexpected token  'mysql -u '.DB_USER.' -p'.DB_PASSWORD.' '.DB_NAME.' table_name < mydomain.com/files/database.sql;'
line 40: exec('mysql -u '.DB_USER.' -p'.DB_PASSWORD.' '.DB_NAME.' table_name < mydomain.com/files/database.sql;');

Can anyone help me resolve this issue?

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