public boolean isLeftmostKey(Field key) throws IOException {
		if (getIdIndex(key) == 0) {
			if (parent != null) {
				return parent.isLeftmostKey(key);
			}
			return true;
		}
		return false;
	}
Move some or all of the keys from the right node into the left node.
If all keys are moved, the caller is responsible for deleting the right
node.
@param leftNode
@param rightNode
@param count
Ghidra/Framework/DB/src/main/java/db/VarKeyInteriorNode.java