# Functions
AggFuncToPBExpr converts aggregate function to pb.
ExplainAggFunc generates explain information for a aggregation function.
NewAggFuncDesc creates an aggregation function signature descriptor.
NewDistAggFunc creates new Aggregate function for mock tikv.
# Constants
CompleteMode function accepts origin data.
FinalMode function accepts partial data.
# Structs
AggEvaluateContext is used to store intermediate result when calculating aggregate functions.
AggFuncDesc describes an aggregation function signature, only used in planner.
# Interfaces
Aggregation stands for aggregate functions.
# Type aliases
AggFunctionMode stands for the aggregation function's mode.