I think you can execute MySQL statements from a text file, for example
here is the cmds.txt file which contains MySQL commands:
select colA from TableA;
select colB from TableB;
select colC from TableC;
To execute them using shell script, type
mysql -h$host -u$user -p$password db_dbname < cmds.txt
This way, you separate your MySQL commands from your shell script.
You may want your script to display progress information to you. For this you can invoke mysql with "--verbose" option.
For more information, see https://dev.mysql.com/doc/refman/5.6/en/mysql-batch-commands.html
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…