Pass Constraint with functional predicate to ConnectorSplitManager

[findepi]

Constraint#predicate represents a Filter that cannot be converted to a TupleDomain.
Today the Constraint#predicate is passed to io.trino.spi.connector.ConnectorMetadata#applyFilter (but only sometimes, i.e. within AddExchanges)
Connector may be unable to derived all the possible information out of that at this stage.
We should pass the same information second time, to ConnectorSplitManager.

[sopel39]

Should we fix planner and connectors instead so that pushdown of predicate via applyFilter is more reliable?

[findepi]

Constraint#predicate is not always present for performance reasons.

[martint]

Are the performance reasons that it can be expensive to evaluate? Then we should improve that, instead. There’s no reason why it should be as slow as it is today — Trino used to evaluate expressions exclusively by interpreting them on the early days, and it was not horrible.

[findepi]

Are the performance reasons that it can be expensive to evaluate? Then we should improve that

Let's track this as a separate issue

instead.

Improving performance wouldn't alleviate the underlying problem that split manager doesn't have access to full information.
For example, HiveTableHandle keeps list of partitions to scan. (It uses memory, so we have a safety limit for 100K partitions).
Now imagine you want to change hive connector not to track partition list explicitly, or you simply delay this computing this
information until the time of split generation. Today it's not possible, as ConnectorSplitManager gets TupleDomain only,
and not Constraint.

[sopel39]

or you simply delay this computing this
information until the time of split generation

We use selected partitions list to generate table predicates.

We could maybe keep Optional<Predicate<Map<ColumnHandle, NullableValue>>> predicate within HiveTableHandle (since it's used only on coordinator)?

[findepi]

We could maybe keep Optional<Predicate<Map<ColumnHandle, NullableValue>>> predicate within HiveTableHandle (since it's used only on coordinator)?

I wanted to start a separate thread about ... #7620

[losipiuk]

cc: @losipiuk