@Override
	public int getKeyIndex(Field key) throws IOException {

		int min = 0;
		int max = keyCount - 1;

		while (min <= max) {
			int i = (min + max) / 2;
			int rc = compareKeyField(key, i);
			if (rc == 0) {
				return i;
			}
			else if (rc > 0) {
				min = i + 1;
			}
			else {
				max = i - 1;
			}
		}
		return -(min + 1);
	}
Get this leaf node's left sibling
@return this leaf node's left sibling or null if left sibling does not exist.
@throws IOException if an IO error occurs
Ghidra/Framework/DB/src/main/java/db/VarKeyRecordNode.java