Unable to fix the logic of the bash script - mysql

Question

I have a table (say UserInputDetails) with the following entries:
+------------+-----------+----------+
| screenId | userInput | numInput |
+------------+-----------+----------+
| 13_1_2_1 | 2 | 9 |
| 13_1_2_2 | 2 | 9 |
| 13_1_2_2 | 3 | 2 |
| 13_1_2_2 | 9 | 2 |
| 13_1_2_2_2 | 3 | 3 |
| 13_1_2_2_2 | 5 | 2 |
| 13_2_2_2 | 4 | 4 |
| 13_2_2_2 | 5 | 4 |
| 13_2_2_2 | 7 | 2 |
+------------+-----------+----------+
I need to write a shell script which gives its expected output as:
13_1_2_1,0,0,9,0,0,0,0,0,0,0
13_1_2_2,0,0,9,2,0,0,0,0,0,2
13_1_2_2_2,0,0,0,3,0,2,0,0,0,0
13_2_2_2,0,0,0,0,4,4,0,2,0,0
Explanation for the output:
the first line of input denotes the numInputs for a particular userInput for screenId '13_1_2_1'. The line first prints the screenId and then corresponding NumInput for userInput 0-9. Since the numInput for userInput '2' is 9 and for the rest of 0-9 is 0, it gives the value 13_1_2_1,0,0,9,0,0,0,0,0,0,0
The bash script written for the following function is:
#!/bin/bash
MYSQL="mysql -uroot -proot -N Database1"
yesterday=""
if [ $# -ge 1 ]
then
yesterday="$1"
else
yesterday=`$MYSQL -sBe "select date_sub(date(now()), interval 1 day);"`
fi
echo "DATE: $yesterday"
PREVSCREENID=''
SCREENID=
ABC=tempSqlDataFile
$MYSQL -sBe "select screenId, userInput, numInput from userInputDetails group by screenID, userInput" > $ABC
for i in {0..9}
do
arr[$i]='0'
done
while read line
do
SCREENID=`echo $line | awk '{ print $1 }'`
i=`echo $line | awk '{print $2 }'`
arr[$i]=`echo $line | awk '{print $3}'`
if [[ $SCREENID != $PREVSCREENID ]]
then
echo "$SCREENID ${arr[*]}" | tr ' ' ','
for i in {0..9}
do
arr[$i]='0'
done
else
i=`echo $line | awk '{print $2 + 1}'`
arr[$i]=`echo $line | awk '{print $3}'`
fi
PREVSCREENID=$SCREENID
done < $ABC
The logic somewhere is going wrong and I am unable to get the logic right. the output from the above shell script is:
13_1_2_1,0,0,9,0,0,0,0,0,0,0,
13_1_2_2,0,0,9,0,0,0,0,0,0,0,
13_1_2_2_2,0,0,9,3,0,0,0,0,0,2,
13_2_2_2,0,0,0,3,4,2,0,0,0,0,
Please can you help me fix the logic in my script? Also, since I am new to scripting and programming, this may not be an efficient way to perform this task. Please suggest if there is an efficient way.

Answer 1

There are a number of errors in your script. Here's a rewrite of the latter part:
while read SCREENID i n; do
if [[ "$SCREENID" != "$PREVSCREENID" ]]; then
[ "$PREVSCREENID" ] && echo "$PREVSCREENID ${arr[*]}" | tr ' ' ,
for j in {0..9}; do arr[$j]=0; done
fi
arr[$i]="$n"
PREVSCREENID="$SCREENID"
done < "$ABC"
echo "$PREVSCREENID ${arr[*]}" | tr ' ' ,
You can avoid calling tr like this:
print_arr() { IFS=,; echo $PREVSCREENID,"${arr[*]}"; unset IFS; }
while read SCREENID i n; do
if [[ "$SCREENID" != "$PREVSCREENID" ]]; then
[ "$PREVSCREENID" ] && print_arr
for j in {0..9}; do arr[$j]=0; done
fi
arr[$i]="$n"
PREVSCREENID="$SCREENID"
done < "$ABC"
print_arr