[Properties (by Name)] [Methods (by Name)] [Events (by Name)]
Internally used class for maximum aggregate functions
Source position: fpexprpars.pp line 666
type TAggregateMax = class(TAggregateExpr) |
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public |
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procedure InitAggregate; override; |
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Initialize maximum aggregation |
procedure UpdateAggregate; override; |
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Update maximum aggregate with new value |
end; |
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Internally used class for maximum aggregate functions |
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Internally used Base class for aggregate expressions |
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Internally used class for representing function calls in expression trees |
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Internally used class for identifier nodes in expression trees |
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Class for representing nodes in expression trees |
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The TAggregateMax class implements the maximum aggregate function, which finds the largest value among all processed values. It extends TAggregateExpr to provide maximum-specific aggregation logic.
The class maintains an internal state that tracks the maximum value encountered so far during the aggregation process. The first value encountered is used as the initial maximum, and subsequent values are compared to update the maximum when larger values are found.
The maximum function works with numeric types (integers, floats, currency) and can also compare string and date/time values using appropriate comparison logic for each data type.
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Class for representing nodes in expression trees |