Add one expression rewrite rule:
rewrite InPredicate to an EqualTo Expression, if there exists exactly one element in InPredicate Options.
Examples:
1. where A in (x) ==> where A = x
2. where A not in (x) ==> where not A = x
- add an interface ExpectsInputTypes to Expression
- add an interface ImplicitCastInputTypes to Expression
- add a Expression rewrite rule for type coercion
- add a Check Analysis Rule to check whether Plan is Semantically correct
if Expression implements ImplicitCastInputTypes, type coercion rule will automatic rewrite its children that casting it to the most suitable type.
If Expression implements ExpectsInputTypes, Check Analysis will check its children's type whether accepted by expects input types.
support view in query
and add a rewrite rule: merge consecutive projects.
the rule can merge relative consecutive projects to one project to improve efficiency
1. add StatementContext, and PlannerContext is renamed to CascadsContext. CascadsContext belong to a StatementContext, and StatementContext belong to a ConnectionContext, and the lifecycle increases in turn. StatementContext can wrap some statement's lifecycle-related state, such as ExpressionId, TableLock. MemoTestUtil can simplify create a CascadesContext and Memo for test.
2. add PlanPreprocessor to process parsed logical plan before copy into memo. and add a PlanPostprocessor to process physical plan after copy out from memo.
3. utilize PlanPreprocessor to process SET_VAR hint, the class is EliminateLogicalSelectHint
4. pass the limit clause in regression test case, in set_var.groovy
1. Add InPredicate expression parser and translator
2. Add regression-test for In predicate (in nereids_syntax)
3. Support NOT EqualTo and NOT InPredicate in ExpressionTranslator#visitNot()
