Table.ApproximateRowCount

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Syntax

Table.ApproximateRowCount(table as table) as number

About

Returns the approximate number of rows in the table, or an error if the data source doesn't support approximation.

Example 1

Estimate the number of distinct combinations of city and state in a large table, which can be used as a cardinality estimate for the columns. Cardinality estimates are important enough that various data sources (such as SQL Server) support this particular approximation, often using an algorithm called HyperLogLog.

Usage

Table.ApproximateRowCount(Table.Distinct(Table.SelectColumns(sqlTable, {"city", "state"})))

Output

number