Macrosยง
- inconsistent_
check ๐
Structsยง
RangeExprRewriter
will recursively search certainExpr
, find allrange_fn
scalar udf contained inExpr
, and collect the information required by the RangeSelect query, and finally modify therange_fn
scalar udf to an ordinary column field.- In order to implement RangeSelect query like
avg(field_0) RANGE '5m' FILL NULL
, All RangeSelect query items are converted into udf scalar function in sql parse stage, with format likerange_fn(avg(field_0), .....)
.range_fn
contains all the parameters we need to execute RangeSelect. In order to correctly execute the query process of range select, we need to modify the query plan generated by datafusion. We need to recursively find the entire LogicalPlan, and find allrange_fn
scalar udf contained in the project plan, collecting info we need to generate RangeSelect Query LogicalPlan and rewrite th original LogicalPlan.
Functionsยง
- dispose_
parse_ ๐error - Evaluate a time calculation expr, case like:
- have_
range_ ๐in_ exprs - parse_
align_ ๐to Parse thealign to
clause and return a UTC timestamp with unit of millisecond, which is used as the basis for dividing time slot during the align operation. - parse_
duration_ ๐expr Parse a duraion expr: - parse_
expr_ ๐list - parse_
expr_ ๐to_ string - parse_
str_ ๐expr