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mean()

Calculate the exact mean from values in a `tdigest`

Since 1.0.0

Calculate the exact mean of the values in a tdigest aggregate. Unlike percentile calculations, the mean calculation is exact. This accessor allows you to calculate the mean alongside percentiles, without needing to create two separate aggregates from the same raw data.

Calculate the mean of the integers from 0 to 100.

SELECT mean(tdigest(data))
FROM generate_series(0, 100) data;
mean
------
50

The syntax is:

mean(
digest TDigest
) RETURNS DOUBLE PRECISION
NameTypeDefaultRequiredDescription
digestTDigest-The tdigest aggregate to extract the mean from
ColumnTypeDescription
meanDOUBLE PRECISIONThe mean of the values in the tdigest.