Escaping MYSQL command lines via Bash Scripting

This seems like a classic case of using the wrong tool for the job.

You've got a lot of work ahead of you to implement the escaping done by mysql_real_escape_string() in bash. Note that mysql_real_escape_string() actually delegates the escaping to the MySQL library which takes into account the connection and database character sets. It's called "real" because its predecessor mysql_escape_string() did not take the character set into consideration, and could be tricked into injecting SQL.

I'd suggest using a scripting language that has a MySQL library, such as Ruby, Python, or PHP.

If you insist on bash, then use the MySQL Prepared Statements syntax.

There is no escape from the following construct, no matter what quotes you use:

PASSWORD=$1
doSQL "INSERT INTO active_records (password) VALUES (FROM_BASE64('$(echo -n $PASSWORD|base64)'))"

In Bash, printf can do the escaping for you:

$ a=''\''"\;:#[]{}()|&^$@!?, .<>abc123'
$ printf -v var "%q" "$a"
$ echo "$var"
\'\"\\\;:#\[\]\{\}\(\)\|\&\^\$@\!\?\,\ .\<\>abc123

I'll leave it to you to decide if that's aggressive enough.