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AggregateFunction

public final class AggregateFunction

A class that represents an aggregate function.

Summary

Nested types
`public static class AggregateFunction.Companion`

Public methods
`final @NonNull AliasedAggregate`	`alias(@NonNull String alias)` Assigns an alias to this aggregate.
`static final @NonNull AggregateFunction`	`arrayAgg(@NonNull Expression expression)` Creates an aggregation that collects all values of an expression across multiple stage inputs into an array.
`static final @NonNull AggregateFunction`	`arrayAgg(@NonNull String fieldName)` Creates an aggregation that collects all values of a field across multiple stage inputs into an array.
`static final @NonNull AggregateFunction`	`arrayAggDistinct(@NonNull Expression expression)` Creates an aggregation that collects all distinct values of an expression across multiple stage inputs into an array.
`static final @NonNull AggregateFunction`	`arrayAggDistinct(@NonNull String fieldName)` Creates an aggregation that collects all distinct values of a field across multiple stage inputs into an array.
`static final @NonNull AggregateFunction`	`average(@NonNull Expression expression)` Creates an aggregation that calculates the average (mean) of values from an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`average(@NonNull String fieldName)` Creates an aggregation that calculates the average (mean) of a field's values across multiple stage inputs.
`static final @NonNull AggregateFunction`	`count(@NonNull Expression expression)` Creates an aggregation that counts the number of stage inputs with valid evaluations of the provided `expression`.
`static final @NonNull AggregateFunction`	`count(@NonNull String fieldName)` Creates an aggregation that counts the number of stage inputs where the input field exists.
`static final @NonNull AggregateFunction`	`countAll()` Creates an aggregation that counts the total number of stage inputs.
`static final @NonNull AggregateFunction`	`countDistinct(@NonNull Expression expression)` Creates an aggregation that counts the number of distinct values of an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`countDistinct(@NonNull String fieldName)` Creates an aggregation that counts the number of distinct values of a field across multiple stage inputs.
`static final @NonNull AggregateFunction`	`countIf(@NonNull BooleanExpression condition)` Creates an aggregation that counts the number of stage inputs where the provided boolean expression evaluates to true.
`static final @NonNull AggregateFunction`	`first(@NonNull Expression expression)` Creates an aggregation that finds the first value of an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`first(@NonNull String fieldName)` Creates an aggregation that finds the first value of a field across multiple stage inputs.
`static final @NonNull AggregateFunction`	`last(@NonNull Expression expression)` Creates an aggregation that finds the last value of an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`last(@NonNull String fieldName)` Creates an aggregation that finds the last value of a field across multiple stage inputs.
`static final @NonNull AggregateFunction`	`maximum(@NonNull Expression expression)` Creates an aggregation that finds the maximum value of an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`maximum(@NonNull String fieldName)` Creates an aggregation that finds the maximum value of a field across multiple stage inputs.
`static final @NonNull AggregateFunction`	`minimum(@NonNull Expression expression)` Creates an aggregation that finds the minimum value of an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`minimum(@NonNull String fieldName)` Creates an aggregation that finds the minimum value of a field across multiple stage inputs.
`static final @NonNull AggregateFunction`	`rawAggregate(@NonNull String name, @NonNull Expression expr)` Creates a raw aggregation function.
`static final @NonNull AggregateFunction`	`sum(@NonNull Expression expression)` Creates an aggregation that calculates the sum of values from an expression across multiple stage inputs.
`static final @NonNull AggregateFunction`	`sum(@NonNull String fieldName)` Creates an aggregation that calculates the sum of a field's values across multiple stage inputs.

Public methods

alias

public final @NonNull AliasedAggregate alias(@NonNull String alias)

Assigns an alias to this aggregate.

Parameters
`@NonNull String alias`	The alias to assign to this aggregate.

Returns
`@NonNull AliasedAggregate`	A new `AliasedAggregate` that wraps this aggregate and associates it with the provided alias.

arrayAgg

public static final @NonNull AggregateFunction arrayAgg(@NonNull Expression expression)

Creates an aggregation that collects all values of an expression across multiple stage inputs into an array.

If the expression resolves to an absent value, it is converted to null. The order of elements in the output array is not stable and shouldn't be relied upon.

Parameters
`@NonNull Expression expression`	The expression to collect values from.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the array_agg aggregation.

arrayAgg

public static final @NonNull AggregateFunction arrayAgg(@NonNull String fieldName)

Creates an aggregation that collects all values of a field across multiple stage inputs into an array.

If the expression resolves to an absent value, it is converted to null. The order of elements in the output array is not stable and shouldn't be relied upon.

Parameters
`@NonNull String fieldName`	The name of the field to collect values from.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the array_agg aggregation.

arrayAggDistinct

public static final @NonNull AggregateFunction arrayAggDistinct(@NonNull Expression expression)

Creates an aggregation that collects all distinct values of an expression across multiple stage inputs into an array.

If the expression resolves to an absent value, it is converted to null. The order of elements in the output array is not stable and shouldn't be relied upon.

Parameters
`@NonNull Expression expression`	The expression to collect values from.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the array_agg_distinct aggregation.

arrayAggDistinct

public static final @NonNull AggregateFunction arrayAggDistinct(@NonNull String fieldName)

Creates an aggregation that collects all distinct values of a field across multiple stage inputs into an array.

If the expression resolves to an absent value, it is converted to null. The order of elements in the output array is not stable and shouldn't be relied upon.

Parameters
`@NonNull String fieldName`	The name of the field to collect values from.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the array_agg_distinct aggregation.

average

public static final @NonNull AggregateFunction average(@NonNull Expression expression)

Creates an aggregation that calculates the average (mean) of values from an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression representing the values to average.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the average aggregation.

average

public static final @NonNull AggregateFunction average(@NonNull String fieldName)

Creates an aggregation that calculates the average (mean) of a field's values across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field containing numeric values to average.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the average aggregation.

count

public static final @NonNull AggregateFunction count(@NonNull Expression expression)

Creates an aggregation that counts the number of stage inputs with valid evaluations of the provided expression.

Parameters
`@NonNull Expression expression`	The expression to count.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the 'count' aggregation.

count

public static final @NonNull AggregateFunction count(@NonNull String fieldName)

Creates an aggregation that counts the number of stage inputs where the input field exists.

Parameters
`@NonNull String fieldName`	The name of the field to count.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the 'count' aggregation.

countAll

public static final @NonNull AggregateFunction countAll()

Creates an aggregation that counts the total number of stage inputs.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the countAll aggregation.

countDistinct

public static final @NonNull AggregateFunction countDistinct(@NonNull Expression expression)

Creates an aggregation that counts the number of distinct values of an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to count the distinct values of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the count distinct aggregation.

countDistinct

public static final @NonNull AggregateFunction countDistinct(@NonNull String fieldName)

Creates an aggregation that counts the number of distinct values of a field across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field to count the distinct values of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the count distinct aggregation.

countIf

public static final @NonNull AggregateFunction countIf(@NonNull BooleanExpression condition)

Creates an aggregation that counts the number of stage inputs where the provided boolean expression evaluates to true.

Parameters
`@NonNull BooleanExpression condition`	The boolean expression to evaluate on each input.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the count aggregation.

first

public static final @NonNull AggregateFunction first(@NonNull Expression expression)

Creates an aggregation that finds the first value of an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to find the first value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the first aggregation.

first

public static final @NonNull AggregateFunction first(@NonNull String fieldName)

Creates an aggregation that finds the first value of a field across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field to find the first value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the first aggregation.

last

public static final @NonNull AggregateFunction last(@NonNull Expression expression)

Creates an aggregation that finds the last value of an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to find the last value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the last aggregation.

last

public static final @NonNull AggregateFunction last(@NonNull String fieldName)

Creates an aggregation that finds the last value of a field across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field to find the last value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the last aggregation.

maximum

public static final @NonNull AggregateFunction maximum(@NonNull Expression expression)

Creates an aggregation that finds the maximum value of an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to find the maximum value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the maximum aggregation.

maximum

public static final @NonNull AggregateFunction maximum(@NonNull String fieldName)

Creates an aggregation that finds the maximum value of a field across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field to find the maximum value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the maximum aggregation.

minimum

public static final @NonNull AggregateFunction minimum(@NonNull Expression expression)

Creates an aggregation that finds the minimum value of an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to find the minimum value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the minimum aggregation.

minimum

public static final @NonNull AggregateFunction minimum(@NonNull String fieldName)

Creates an aggregation that finds the minimum value of a field across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field to find the minimum value of.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the minimum aggregation.

rawAggregate

public static final @NonNull AggregateFunction rawAggregate(@NonNull String name, @NonNull Expression expr)

Creates a raw aggregation function.

This method provides a way to call aggregation functions that are supported by the Firestore backend but that are not available as specific factory methods in this class.

Parameters
`@NonNull String name`	The name of the aggregation function.
`@NonNull Expression expr`	The expressions to pass as arguments to the function.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` for the specified function.

sum

public static final @NonNull AggregateFunction sum(@NonNull Expression expression)

Creates an aggregation that calculates the sum of values from an expression across multiple stage inputs.

Parameters
`@NonNull Expression expression`	The expression to sum up.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the sum aggregation.

sum

public static final @NonNull AggregateFunction sum(@NonNull String fieldName)

Creates an aggregation that calculates the sum of a field's values across multiple stage inputs.

Parameters
`@NonNull String fieldName`	The name of the field containing numeric values to sum up.

Returns
`@NonNull AggregateFunction`	A new `AggregateFunction` representing the sum aggregation.

AggregateFunction

Summary

Nested types

Public methods

Public methods

alias

arrayAgg

arrayAgg

arrayAggDistinct

arrayAggDistinct

average

average

count

count

countAll

countDistinct

countDistinct

countIf

first

first

last

last

maximum

maximum

minimum

minimum

rawAggregate

sum

sum