public int countKey(K key) {
		Field encoded = codec.encodeField(key);
		if (!fieldSpan.containsPoint(encoded)) {
			return 0;
		}
		return countKey(encoded);
	}
Count the number of objects whose indexed field has the given value

@param key the value
@return the count
Ghidra/Debug/ProposedUtils/src/main/java/ghidra/util/database/DBCachedObjectIndex.java