ovs_find_and_delete.sh

# User specific aliases and functions
function ovs_destroy_find() {
    local cmd=$1
    local table=$2
    local condition=$3
    eval $cmd "-- destroy $table "{$(ovs-vsctl --no-headings --columns=_uuid -f csv find $table $condition|paste -sd",")}
}

alias nbdf="ovs_destroy_find ovn-nbctl"
alias sbdf="ovs_destroy_find ovn-sbctl"
alias ovsdf="ovs_destroy_find ovs-vsctl"

Example:
Delete all QoS table entries with a type=test:

ovsdf QoS type=test

Delete all QoS table entries:

ovsdf QoS

(though for deleting everything in a table you could do $cmd --all destroy $table as well)
etc.