OPAL Time Functions

Time functions provide conversion to and from various time and date formats.

Function	Description
abs	Returns the absolute value of ‘val’.
avg	Calculate the arithmetic average of the input expression across the group, or of the scalar arguments if more than one.
bin_end_time	Returns the end time of the current bin (exclusive).
bin_size	Returns the size of the time bin that’s being aggregated.
bin_start_time	Returns the start time of the current bin (inclusive).
delta	Calculates the value difference of the argument in each time bin for each group.
delta_monotonic	Calculates the amount of difference in a column in each time bin for each group.
deriv	Calculate the average per-second derivative of the argument across the group.
duration	Convert one argument as a number of nanoseconds or a timestamp, or two arguments as start or stop timestamps, to a duration.
duration_hr	The input is a number representing a number of hours, the output is that quantity as type duration.
duration_min	The input is a number representing a number of minutes, the output is that quantity as type duration.
duration_ms	The input is a number representing a number of milliseconds, the output is that quantity as type duration.
duration_null	Returns a null value of type duration.
duration_sec	The input is a number representing a number of seconds, the output is that quantity as type duration.
format_time	Format a timestamp column according to the specified format string.
from_milliseconds	Given a numeric value representing milliseconds since epoch, return a timestamp of that point in time.
from_nanoseconds	Given a numeric value representing nanoseconds since epoch, return a timestamp of that point in time.
from_seconds	Given a numeric value representing seconds since epoch, return a timestamp of that point in time.
median	Return the fast approximate median value of one column.
median_exact	Return the exact median value of one column.
now	Returns the current time for which the query is executed as timestamp.
parse_duration	Given a string describing the duration between two points in time, convert it to a duration.
parse_isotime	Parse an ISO8601 (YYYY-MM-DDTHH:MM:SSZ) formatted string as a timestamp.
parse_timestamp	Parse a string value, whose format is specified by the format argument, as a timestamp.
percentile	Returns an approximated value for the specified percentile of the input expression across the group.
percentile_cont	Assuming a continuous distribution, return the value for the specified percentile of the input expression across the group.
percentile_disc	Assuming a discrete distribution, return the value for the specified percentile of the input expression across the group.
query_end_time	Returns the latest time of the query time window.
query_start_time	Returns the earliest time of the query time window.
rate	Calculate the average per-second rate of the argument across the group.
row_end_time	Returns the value of the “Valid To” column, or null if the verb input dataset has no “Valid To” column.
row_timestamp	Returns the value of the timestamp column for each row.
stddev	Calculate the standard deviation across the group.
sum	Calculate the sum of the argument across the group, or of the scalar arguments if more than one.
tdigest_agg	Generate a single t-digest state out of an arbitrary number of numeric values.
tdigest_quantile	Calculates a quantile from a TDigest state.
timestamp_null	Returns a null value of type timestamp.
to_days	Convert a duration to a number of days.
to_hours	Convert a duration to a number of hours.
to_milliseconds	Convert a duration to a number of milliseconds.
to_minutes	Convert a duration to a number of minutes.
to_nanoseconds	Convert a duration to a number of nanoseconds.
to_seconds	Convert a duration to a number of seconds.
to_weeks	Convert a duration to a number of weeks.
valid_for	Specify the validity period for each event for some verbs