queryReduce

Reduces query columns just like in array or collection

queryReduce(query, function(result, row [, currentRow] [, query]){} [, initialVal]) → returns any

Argument Reference

query query
Required

query to process entries from

callback any
Required

Closure or a function reference that will be called for each of the iteration.

Callback parameters:

result* any : The result of the reduce operation after the previous iteration
row* struct : A struct with all of the columns for the current iteration
currentRow* numeric : The value for the current iteration
query* query : A reference of the original query

initialValue any

initial value passed as part of the first closure call

Links more information about queryReduce

Map, Reduce and other Higher Order Functions - A Primer for map, reduce, filter, and Higher Order Functions in general.
ColdFusion 2016: query iteration functions - A look at the higher-order functions that queries have

Examples
Sample code invoking the queryReduce function

Reduce column to total

Sum one query column

fruits = queryNew("fruit,amount",
    	"varchar,integer", [{
    		"fruit": "apples",
    		"amount": 15
    	}, {
    		"fruit": "pineapples",
    		"amount": 3
    	}, {
    		"fruit": "strawberries",
    		"amount": 32
    	}]
    );
    total_fruits = queryReduce(fruits,function(a,b) {
        return a + b.amount;
    },0);
    
    writeOutput(total_fruits);

Expected Result: 50

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