Select With Key

Get only items that have non-null values for a specified key

cat data.json | jq -c 'select(.keyName)'

cat data.json | jq -c 'select(.keyName and .otherKey)'

cat data.json | jq -c 'select(.keyName == "value")'

cat data.json | jq -c 'select(.keyName and .otherKey != "value")'