yq/pkg/yqlib/doc/Select.md

Select is used to filter arrays and maps by a boolean expression.

Select elements from array

Given a sample.yml file of:

- cat
- goat
- dog

then

yq eval '.[] | select(. == "*at")' sample.yml

will output

cat
goat

Select and update matching values in map

Given a sample.yml file of:

a: {things: cat, bob: goat, horse: dog}
'': null

then

yq eval '(.a.[] | select(. == "*at")) |= "rabbit"' sample.yml

will output

a: {things: rabbit, bob: rabbit, horse: dog}
'': null