Add Echo A Message From A SQL File as a MySQL TIL

mysql/echo-a-message-from-a-sql-file.md

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+# Echo A Message From A SQL File
+
+Let's say we have a SQL file that we run to seed our database. We want to echo
+a message to stdout at the beginning of that file's execution. We can do this
+with [a MySQL client _shell
+command_](https://dev.mysql.com/doc/mysql-shell/8.0/en/mysql-shell-commands.html).
+Specifically, we need to use the `\system` or `\!` command to run our system's
+`echo` command.
+
+Here is what that could look like:
+
+```sql
+\! echo '*****************************************'
+\! echo '*                                       *'
+\! echo '*  Loading seed data into the database  *'
+\! echo '*                                       *'
+\! echo '*****************************************'
+
+insert into products ...
+```
+
+That message banner will be output when you run the script.
+
+```bash
+$ mysql -h ::1 -P 3306 -u root -D local_database < seed_data.sql
+
+*****************************************
+*                                       *
+*  Loading seed data into the database  *
+*                                       *
+*****************************************
+```