Assign AWK result to variable

Question

This should be pretty straightfoward and I don't know why I am struggling with it.

I am running the following psql command from within a shell script in order to find out whether all indexes have been dropped before inserting data.

INDEXCOUNT=$(psql -p $dbPort -U enterprisedb -d main_db -c "select Count(*) from all_indexes where index_schema = 'enterprisedb';")

At this point, INDEXCOUNT is equal to “COUNT ------- 0”

Now if I echo the following line I get the result I want -

echo $INDEXCOUNT | awk '{print $3}'

How do I assign the value of $INDEXCOUNT | awk ‘{print $3}’ to a variable to check it in an “IF” statement?

For example:

RETURNCOUNT=$INDEXCOUNT | awk '{print $3}'

score 79 · Accepted Answer · answered May 17 '11 at 13:39

79

The following works correctly on bash:

 a=$(echo '111 222 33' | awk '{print $3;}' )
 echo $a # result is "33"

Another option would be to convert the string to an array:

 a="111 222 333"
 b=($a)

 echo ${b[2]}  # returns 333

answered May 17 '11 at 13:39

nimrodm

2

RETURNCOUNT=$(echo $INDEXCOUNT | awk '{print $3}') – user739866 May 17 '11 at 13:45

score 1 · Answer 2 · edited Jul 05 '16 at 19:02

1

You can try this:

RETURNCOUNT=`echo $INDEXCOUNT | awk '{print $3}'`

The idea is to include any shell command between backticks to get the result into a variable.

edited Jul 05 '16 at 19:02

brandizzi

answered May 17 '11 at 13:48

Mayank

`"$INDEXCOUNT"` is unlikely to be a command. – glenn jackman May 17 '11 at 14:19
@glenn: In that case do echo can be used... The idea is to include any shell command between backticks to get the result into a variable – Mayank May 17 '11 at 15:50
2

`$()` is preferred over `backticks` as it makes nesting commands easier – Silviu Aug 16 '12 at 09:22
Although this code may be help to solve the problem, providing additional context regarding _why_ and/or _how_ it answers the question would significantly improve its long-term value. Please [edit] your answer to add some explanation. – Toby Speight Jul 04 '16 at 16:33

score 0 · Answer 3 · edited Jul 04 '16 at 10:45

0

This might be easier to use for testing with if statement/

INDEXCOUNT="111 222 333"
echo $INDEXCOUNT | awk '{if ($3 == 333) print $3}';

edited Jul 04 '16 at 10:45

fedorqui

answered Jul 04 '16 at 10:43

GoggiP

score 0 · Answer 4 · answered May 17 '11 at 20:56

0

Or you can directly use:

${INDEXCOUNT##* }

answered May 17 '11 at 20:56

Dimitre Radoulov

4 Answers4