static byte getIndexFieldType(Field indexedFieldType, Field primaryKeyFieldType) {
		if (primaryKeyFieldType instanceof IndexField) {
			throw new IllegalArgumentException();
		}
		if (indexedFieldType instanceof IndexField) {
			throw new IllegalArgumentException();
		}
		return (byte) ((primaryKeyFieldType.getFieldType() << INDEX_FIELD_TYPE_SHIFT) |
			indexedFieldType.getFieldType());

	}
Construct a new {@link IndexField} instance for the given indexValue and 
associated primary key.  These fields are verified against this instance to 
ensure that they are of the correct type.
@param indexValue column field value to be indexed
@param key primary key associated with indexValue
@return new IndexField instance
Ghidra/Framework/DB/src/main/java/db/IndexField.java