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AggregateFunction.Companion

public static class AggregateFunction.Companion

Summary

Public methods
`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`	`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

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.

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.