perf improvements since 0.13.0?
I just ran `./test_perf.sh -b v0.13.0 -t HEAD -r '.*query.*'` and this is what I got:

```
-------------------------------------------------------------------------------
Test name                                    | head[ms] | base[ms] |  ratio   |
-------------------------------------------------------------------------------
query_datetime_index                         |   7.5057 | 375.5414 |   0.0200 |
query_datetime_series                        |   7.4463 |  12.2663 |   0.6071 |
query_with_boolean_selection                 |  14.4973 |  17.2227 |   0.8418 |
-------------------------------------------------------------------------------
Test name                                    | head[ms] | base[ms] |  ratio   |
-------------------------------------------------------------------------------
```

want to make sure this is expected
