How to optimize the following script - bash

Question

This script runs a query to get a list of dates and runs two other queries for these dates.
Then compares which one is the smaller of the numbers and multiplies it by 2.
Then writes to file and sums them.
Please suggest improvements. Also checks for 0 numbers.
#!/bin/bash
1>output.txt
today=$(date +"%Y%m%d")
FirstOfTheMonth=$(date -d "--$(($(date +%-d)-1)) day" `enter code here`+"%Y%m%d")
echo "XXXX activity report on daily and cumulative monthly `enter code here`basis "
#query that outputs dates to a file
SQL query > list
#for each date I run 2 queries
for i in `cat list`;do
a1=SQL query;
b1=SQL query;
# I compare to find out which one is the smaller number and `enter code here`multiply it by 2
buy=${a1#-}
sell=${b1#-}
echo "XXX report for $yesterday month = $i "
echo "Buy $buy"
echo "Sell $sell"
if [ "$buy" -lt "$sell" ];
then DayNumber=$[buy * 2];
else DayNumber=$[sell * 2];
fi;
#I write all the numbers to a file since I have to sum them
MonthNumber=`awk '{ sum += $1 } END { print sum }' `enter `enter code here`code here`DayNumber$i`
echo "Day Number $DayNumber"
echo "$DayNumber$i $MonthNumber$1 $yesterday" >> DayNumber$i
echo "Day Number since $FirstOfTheMonth $MonthNumber$1"
echo ---------------------------------------------------------------------------------------
done
/usr/bin/mail -s "XXXX report $today" xxx#xxxx.com < `enter code here`output.txt

Answer 1

You are most likely getting down votes, do to the size of the code, lack of clarity on what you want, not showing effort to get that result on your own, and very rudimentary mistakes in code readability that could be fixed with a web search for a tutorial. Google has a shell style guide that you should read.
If you are redirecting stdout to a file, you are probably running autonomously. Which means you should redirect stderr too.
exec &>output.txt
First of the month-- not sure why you don't just do this
FirstOfTheMonth=$(date +%Y%m1)
For Pete's sake, indent! This makes me want to beat scripters. Also, don't use i unless it's a very small loop. Use a variable that means something.
while read -rd' ' month; do
some commands
if [[ $buy -lt $sell ]]; then
do this thing here
fi
done
Bash isn't semi-colon terminated, you don't need one at the end of a line. Use the interan [[ ]] over the externam [ ]. Don't quote a variable (e.g. "$buy") to do a numeric comparison (e.g. -lt). Keep your then on the same line as if-- it servers no other purpose than to make it more readable.