Table 4.

Q-error, MAE, and SMAPE of different cardinality estimators with the IMDB dataset.

Method	Q-Error	MAE	SMAPE
PostgreSQL	2 × ${10}^5$	/	/
MySQL	2 × ${10}^5$	/	/
VSCNN	3.12	2291	0.59
MSCN (string)	1.94	2176	0.31
NoSamplingTreeLSTM	10.37	5387	0.89
NoSamplingTreeLSTM	2.38	1959	0.33
TreeLSTM (ours)	1.63	1109	0.19