Functions for Working with Dates and Times
Most functions in this section accept an optional time zone argument, e.g. Europe/Amsterdam
. In this case, the time zone is the specified one instead of the local (default) one.
Example
makeDate
Creates a Date
- from a year, month and day argument, or
- from a year and day of year argument.
Syntax
Alias:
MAKEDATE(year, month, day);
MAKEDATE(year, day_of_year);
Arguments
year
— Year. Integer, Float or Decimal.month
— Month. Integer, Float or Decimal.day
— Day. Integer, Float or Decimal.day_of_year
— Day of the year. Integer, Float or Decimal.
Returned value
- A date created from the arguments. Date.
Example
Create a Date from a year, month and day:
Result:
Create a Date from a year and day of year argument:
Result:
makeDate32
Creates a date of type Date32 from a year, month, day (or optionally a year and a day).
Syntax
Arguments
year
— Year. Integer, Float or Decimal.month
— Month (optional). Integer, Float or Decimal.day
— Day. Integer, Float or Decimal.
If month
is omitted then day
should take a value between 1
and 365
, otherwise it should take a value between 1
and 31
.
Returned values
- A date created from the arguments. Date32.
Examples
Create a date from a year, month, and day:
Query:
Result:
Create a Date from a year and day of year:
Query:
Result:
makeDateTime
Creates a DateTime from a year, month, day, hour, minute and second argument.
Syntax
Arguments
year
— Year. Integer, Float or Decimal.month
— Month. Integer, Float or Decimal.day
— Day. Integer, Float or Decimal.hour
— Hour. Integer, Float or Decimal.minute
— Minute. Integer, Float or Decimal.second
— Second. Integer, Float or Decimal.timezone
— Timezone for the returned value (optional).
Returned value
- A date with time created from the arguments. DateTime.
Example
Result:
makeDateTime64
Creates a DateTime64 data type value from its components: year, month, day, hour, minute, second. With optional sub-second precision.
Syntax
Arguments
year
— Year (0-9999). Integer, Float or Decimal.month
— Month (1-12). Integer, Float or Decimal.day
— Day (1-31). Integer, Float or Decimal.hour
— Hour (0-23). Integer, Float or Decimal.minute
— Minute (0-59). Integer, Float or Decimal.second
— Second (0-59). Integer, Float or Decimal.precision
— Optional precision of the sub-second component (0-9). Integer.
Returned value
- A date and time created from the supplied arguments. DateTime64.
Example
timestamp
Converts the first argument 'expr' to type DateTime64(6). If a second argument 'expr_time' is provided, it adds the specified time to the converted value.
Syntax
Alias: TIMESTAMP
Arguments
Examples
Result:
Result:
Returned value
- DateTime64(6)
timeZone
Returns the timezone of the current session, i.e. the value of setting session_timezone. If the function is executed in the context of a distributed table, then it generates a normal column with values relevant to each shard, otherwise it produces a constant value.
Syntax
Alias: timezone
.
Returned value
- Timezone. String.
Example
Result:
See also
serverTimeZone
Returns the timezone of the server, i.e. the value of setting timezone. If the function is executed in the context of a distributed table, then it generates a normal column with values relevant to each shard. Otherwise, it produces a constant value.
Syntax
Alias: serverTimezone
.
Returned value
- Timezone. String.
Example
Result:
See also
toTimeZone
Converts a date or date with time to the specified time zone. Does not change the internal value (number of unix seconds) of the data, only the value's time zone attribute and the value's string representation changes.
Syntax
Alias: toTimezone
.
Arguments
value
— Time or date and time. DateTime64.timezone
— Timezone for the returned value. String. This argument is a constant, becausetoTimezone
changes the timezone of a column (timezone is an attribute ofDateTime*
types).
Returned value
- Date and time. DateTime.
Example
Result:
See Also
- formatDateTime - supports non-constant timezone.
- toString - supports non-constant timezone.
timeZoneOf
Returns the timezone name of DateTime or DateTime64 data types.
Syntax
Alias: timezoneOf
.
Arguments
value
— Date and time. DateTime or DateTime64.
Returned value
- Timezone name. String.
Example
Result:
timeZoneOffset
Returns the timezone offset in seconds from UTC. The function daylight saving time and historical timezone changes at the specified date and time into account. The IANA timezone database is used to calculate the offset.
Syntax
Alias: timezoneOffset
.
Arguments
value
— Date and time. DateTime or DateTime64.
Returned value
- Offset from UTC in seconds. Int32.
Example
Result:
toYear
Returns the year component (AD) of a date or date with time.
Syntax
Alias: YEAR
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The year of the given date/time. UInt16.
Example
Result:
toQuarter
Returns the quarter (1-4) of a date or date with time.
Syntax
Alias: QUARTER
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The quarter of the year (1, 2, 3 or 4) of the given date/time. UInt8.
Example
Result:
toMonth
Returns the month component (1-12) of a date or date with time.
Syntax
Alias: MONTH
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The month of the year (1 - 12) of the given date/time. UInt8.
Example
Result:
toDayOfYear
Returns the number of the day within the year (1-366) of a date or date with time.
Syntax
Alias: DAYOFYEAR
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The day of the year (1 - 366) of the given date/time. UInt16.
Example
Result:
toDayOfMonth
Returns the number of the day within the month (1-31) of a date or date with time.
Syntax
Aliases: DAYOFMONTH
, DAY
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The day of the month (1 - 31) of the given date/time. UInt8.
Example
Result:
toDayOfWeek
Returns the number of the day within the week of a date or date with time.
The two-argument form of toDayOfWeek()
enables you to specify whether the week starts on Monday or Sunday, and whether the return value should be in the range from 0 to 6 or 1 to 7. If the mode argument is omitted, the default mode is 0. The time zone of the date can be specified as the third argument.
Mode | First day of week | Range |
---|---|---|
0 | Monday | 1-7: Monday = 1, Tuesday = 2, ..., Sunday = 7 |
1 | Monday | 0-6: Monday = 0, Tuesday = 1, ..., Sunday = 6 |
2 | Sunday | 0-6: Sunday = 0, Monday = 1, ..., Saturday = 6 |
3 | Sunday | 1-7: Sunday = 1, Monday = 2, ..., Saturday = 7 |
Syntax
Alias: DAYOFWEEK
.
Arguments
t
- a Date, Date32, DateTime or DateTime64mode
- determines what the first day of the week is. Possible values are 0, 1, 2 or 3. See the table above for the differences.timezone
- optional parameter, it behaves like any other conversion function
The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.
Returned value
- The day of the week (1-7), depending on the chosen mode, of the given date/time
Example
The following date is April 21, 2023, which was a Friday:
Result:
toHour
Returns the hour component (0-24) of a date with time.
Assumes that if clocks are moved ahead, it is by one hour and occurs at 2 a.m., and if clocks are moved back, it is by one hour and occurs at 3 a.m. (which is not always exactly when it occurs - it depends on the timezone).
Syntax
Alias: HOUR
Arguments
value
- a DateTime or DateTime64
Returned value
- The hour of the day (0 - 23) of the given date/time. UInt8.
Example
Result:
toMinute
Returns the minute component (0-59) a date with time.
Syntax
Alias: MINUTE
Arguments
value
- a DateTime or DateTime64
Returned value
- The minute of the hour (0 - 59) of the given date/time. UInt8.
Example
Result:
toSecond
Returns the second component (0-59) of a date with time. Leap seconds are not considered.
Syntax
Alias: SECOND
Arguments
value
- a DateTime or DateTime64
Returned value
- The second in the minute (0 - 59) of the given date/time. UInt8.
Example
Result:
toMillisecond
Returns the millisecond component (0-999) of a date with time.
Syntax
Arguments*
value
- DateTime or DateTime64
Alias: MILLISECOND
Result:
Returned value
- The millisecond in the minute (0 - 59) of the given date/time. UInt16.
toUnixTimestamp
Converts a string, a date or a date with time to the Unix Timestamp in UInt32
representation.
If the function is called with a string, it accepts an optional timezone argument.
Syntax
Returned value
- Returns the unix timestamp. UInt32.
Example
Result:
The return type of toStartOf*
, toLastDayOf*
, toMonday
, timeSlot
functions described below is determined by the configuration parameter enable_extended_results_for_datetime_functions which is 0
by default.
Behavior for
enable_extended_results_for_datetime_functions = 0
:- Functions
toStartOfYear
,toStartOfISOYear
,toStartOfQuarter
,toStartOfMonth
,toStartOfWeek
,toLastDayOfWeek
,toLastDayOfMonth
,toMonday
returnDate
orDateTime
. - Functions
toStartOfDay
,toStartOfHour
,toStartOfFifteenMinutes
,toStartOfTenMinutes
,toStartOfFiveMinutes
,toStartOfMinute
,timeSlot
returnDateTime
. Though these functions can take values of the extended typesDate32
andDateTime64
as an argument, passing them a time outside the normal range (year 1970 to 2149 forDate
/ 2106 forDateTime
) will produce wrong results.
- Functions
enable_extended_results_for_datetime_functions = 1
:- Functions
toStartOfYear
,toStartOfISOYear
,toStartOfQuarter
,toStartOfMonth
,toStartOfWeek
,toLastDayOfWeek
,toLastDayOfMonth
,toMonday
returnDate
orDateTime
if their argument is aDate
orDateTime
, and they returnDate32
orDateTime64
if their argument is aDate32
orDateTime64
. - Functions
toStartOfDay
,toStartOfHour
,toStartOfFifteenMinutes
,toStartOfTenMinutes
,toStartOfFiveMinutes
,toStartOfMinute
,timeSlot
returnDateTime
if their argument is aDate
orDateTime
, and they returnDateTime64
if their argument is aDate32
orDateTime64
.
- Functions
toStartOfYear
Rounds down a date or date with time to the first day of the year. Returns the date as a Date
object.
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The first day of the year of the input date/time. Date.
Example
Result:
toStartOfISOYear
Rounds down a date or date with time to the first day of the ISO year, which can be different than a "regular" year. (See https://en.wikipedia.org/wiki/ISO_week_date.)
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The first day of the year of the input date/time. Date.
Example
Result:
toStartOfQuarter
Rounds down a date or date with time to the first day of the quarter. The first day of the quarter is either 1 January, 1 April, 1 July, or 1 October. Returns the date.
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The first day of the quarter of the given date/time. Date.
Example
Result:
toStartOfMonth
Rounds down a date or date with time to the first day of the month. Returns the date.
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The first day of the month of the given date/time. Date.
Example
Result:
The behavior of parsing incorrect dates is implementation specific. ClickHouse may return zero date, throw an exception, or do "natural" overflow.
toLastDayOfMonth
Rounds a date or date with time to the last day of the month. Returns the date.
Syntax
Alias: LAST_DAY
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The last day of the month of the given date/time=. Date.
Example
Result:
toMonday
Rounds down a date or date with time to the nearest Monday. Returns the date.
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The date of the nearest Monday on or prior to the given date. Date.
Example
Result:
toStartOfWeek
Rounds a date or date with time down to the nearest Sunday or Monday. Returns the date. The mode argument works exactly like the mode argument in function toWeek()
. If no mode is specified, it defaults to 0.
Syntax
Arguments
t
- a Date, Date32, DateTime or DateTime64mode
- determines the first day of the week as described in the toWeek() functiontimezone
- Optional parameter, it behaves like any other conversion function
Returned value
- The date of the nearest Sunday or Monday on or prior to the given date, depending on the mode. Date.
Example
Result:
toLastDayOfWeek
Rounds a date or date with time up to the nearest Saturday or Sunday. Returns the date.
The mode argument works exactly like the mode argument in function toWeek()
. If no mode is specified, mode is assumed as 0.
Syntax
Arguments
t
- a Date, Date32, DateTime or DateTime64mode
- determines the last day of the week as described in the toWeek functiontimezone
- Optional parameter, it behaves like any other conversion function
Returned value
- The date of the nearest Sunday or Monday on or after the given date, depending on the mode. Date.
Example
Result:
toStartOfDay
Rounds down a date with time to the start of the day.
Syntax
Arguments
value
- a Date, Date32, DateTime or DateTime64
Returned value
- The start of the day of the given date/time. DateTime.
Example
Result:
toStartOfHour
Rounds down a date with time to the start of the hour.
Syntax
Arguments
value
- a DateTime or DateTime64
Returned value
- The start of the hour of the given date/time. DateTime.
Example
Result:
toStartOfMinute
Rounds down a date with time to the start of the minute.
Syntax
Arguments
value
- a DateTime or DateTime64
Returned value
- The start of the minute of the given date/time. DateTime.
Example
Result:
toStartOfSecond
Truncates sub-seconds.
Syntax
Arguments
value
— Date and time. DateTime64.timezone
— Timezone for the returned value (optional). If not specified, the function uses the timezone of thevalue
parameter. String.
Returned value
- Input value without sub-seconds. DateTime64.
Examples
Query without timezone:
Result:
Query with timezone:
Result:
See also
- Timezone server configuration parameter.
toStartOfMillisecond
Rounds down a date with time to the start of the milliseconds.
Syntax
Arguments
value
— Date and time. DateTime64.timezone
— Timezone for the returned value (optional). If not specified, the function uses the timezone of thevalue
parameter. String.
Returned value
- Input value with sub-milliseconds. DateTime64.
Examples
Query without timezone:
Result:
Query with timezone:
Result:
toStartOfMicrosecond
Rounds down a date with time to the start of the microseconds.
Syntax
Arguments
value
— Date and time. DateTime64.timezone
— Timezone for the returned value (optional). If not specified, the function uses the timezone of thevalue
parameter. String.
Returned value
- Input value with sub-microseconds. DateTime64.
Examples
Query without timezone:
Result:
Query with timezone:
Result:
See also
- Timezone server configuration parameter.
toStartOfNanosecond
Rounds down a date with time to the start of the nanoseconds.
Syntax
Arguments
value
— Date and time. DateTime64.timezone
— Timezone for the returned value (optional). If not specified, the function uses the timezone of thevalue
parameter. String.
Returned value
- Input value with nanoseconds. DateTime64.
Examples
Query without timezone:
Result:
Query with timezone:
Result:
See also
- Timezone server configuration parameter.
toStartOfFiveMinutes
Rounds down a date with time to the start of the five-minute interval.
Syntax
Arguments
value
- a DateTime or DateTime64
Returned value
- The start of the five-minute interval of the given date/time. DateTime.
Example
Result:
toStartOfTenMinutes
Rounds down a date with time to the start of the ten-minute interval.
Syntax
Arguments
value
- a DateTime or DateTime64
Returned value
- The start of the ten-minute interval of the given date/time. DateTime.
Example
Result:
toStartOfFifteenMinutes
Rounds down the date with time to the start of the fifteen-minute interval.
Syntax
Arguments
value
- a DateTime or DateTime64
Returned value
- The start of the fifteen-minute interval of the given date/time. DateTime.
Example
Result:
toStartOfInterval
This function generalizes other toStartOf*()
functions with toStartOfInterval(date_or_date_with_time, INTERVAL x unit [, time_zone])
syntax.
For example,
toStartOfInterval(t, INTERVAL 1 YEAR)
returns the same astoStartOfYear(t)
,toStartOfInterval(t, INTERVAL 1 MONTH)
returns the same astoStartOfMonth(t)
,toStartOfInterval(t, INTERVAL 1 DAY)
returns the same astoStartOfDay(t)
,toStartOfInterval(t, INTERVAL 15 MINUTE)
returns the same astoStartOfFifteenMinutes(t)
.
The calculation is performed relative to specific points in time:
Interval | Start |
---|---|
YEAR | year 0 |
QUARTER | 1900 Q1 |
MONTH | 1900 January |
WEEK | 1970, 1st week (01-05) |
DAY | 1970-01-01 |
HOUR | (*) |
MINUTE | 1970-01-01 00:00:00 |
SECOND | 1970-01-01 00:00:00 |
MILLISECOND | 1970-01-01 00:00:00 |
MICROSECOND | 1970-01-01 00:00:00 |
NANOSECOND | 1970-01-01 00:00:00 |
(*) hour intervals are special: the calculation is always performed relative to 00:00:00 (midnight) of the current day. As a result, only hour values between 1 and 23 are useful.
If unit WEEK
was specified, toStartOfInterval
assumes that weeks start on Monday. Note that this behavior is different from that of function toStartOfWeek
in which weeks start by default on Sunday.
Syntax
Aliases: time_bucket
, date_bin
.
The second overload emulates TimescaleDB's time_bucket()
function, respectively PostgreSQL's date_bin()
function, e.g.
Result:
See Also
toTime
Converts a date with time to a certain fixed date, while preserving the time.
Syntax
Arguments
date
— Date to convert to a time. Date/DateTime/DateTime64.timezone
(optional) — Timezone for the returned value. String.
Returned value
- DateTime with date equated to
1970-01-02
while preserving the time. DateTime.
If the date
input argument contained sub-second components,
they will be dropped in the returned DateTime
value with second-accuracy.
Example
Query:
Result:
toRelativeYearNum
Converts a date, or date with time, to the number of years elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of years from a fixed reference point in the past. UInt16.
Example
Query:
Result:
toRelativeQuarterNum
Converts a date, or date with time, to the number of quarters elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of quarters from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeMonthNum
Converts a date, or date with time, to the number of months elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of months from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeWeekNum
Converts a date, or date with time, to the number of weeks elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of weeks from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeDayNum
Converts a date, or date with time, to the number of days elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of days from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeHourNum
Converts a date, or date with time, to the number of hours elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of hours from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeMinuteNum
Converts a date, or date with time, to the number of minutes elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of minutes from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toRelativeSecondNum
Converts a date, or date with time, to the number of the seconds elapsed since a certain fixed point in the past.
Syntax
Arguments
date
— Date or date with time. Date/DateTime/DateTime64.
Returned value
- The number of seconds from a fixed reference point in the past. UInt32.
Example
Query:
Result:
toISOYear
Converts a date, or date with time, to the ISO year as a UInt16 number.
Syntax
Arguments
value
— The value with date or date with time. Date, Date32, DateTime or DateTime64
Returned value
- The input value converted to a ISO year number. UInt16.
Example
Query:
Result:
toISOWeek
Converts a date, or date with time, to a UInt8 number containing the ISO Week number.
Syntax
Arguments
value
— The value with date or date with time.
Returned value
value
converted to the current ISO week number. UInt8.
Example
Query:
Response:
toWeek
This function returns the week number for date or datetime. The two-argument form of toWeek()
enables you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range from 0 to 53 or from 1 to 53. If the mode argument is omitted, the default mode is 0.
toISOWeek()
is a compatibility function that is equivalent to toWeek(date,3)
.
The following table describes how the mode argument works.
Mode | First day of week | Range | Week 1 is the first week ... |
---|---|---|---|
0 | Sunday | 0-53 | with a Sunday in this year |
1 | Monday | 0-53 | with 4 or more days this year |
2 | Sunday | 1-53 | with a Sunday in this year |
3 | Monday | 1-53 | with 4 or more days this year |
4 | Sunday | 0-53 | with 4 or more days this year |
5 | Monday | 0-53 | with a Monday in this year |
6 | Sunday | 1-53 | with 4 or more days this year |
7 | Monday | 1-53 | with a Monday in this year |
8 | Sunday | 1-53 | contains January 1 |
9 | Monday | 1-53 | contains January 1 |
For mode values with a meaning of "with 4 or more days this year," weeks are numbered according to ISO 8601:1988:
-
If the week containing January 1 has 4 or more days in the new year, it is week 1.
-
Otherwise, it is the last week of the previous year, and the next week is week 1.
For mode values with a meaning of "contains January 1", the week contains January 1 is week 1. It does not matter how many days in the new year the week contained, even if it contained only one day. I.e. if the last week of December contains January 1 of the next year, it will be week 1 of the next year.
Syntax
Alias: WEEK
Arguments
t
– Date or DateTime.mode
– Optional parameter, Range of values is [0,9], default is 0.Timezone
– Optional parameter, it behaves like any other conversion function.
The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.
Example
toYearWeek
Returns year and week for a date. The year in the result may be different from the year in the date argument for the first and the last week of the year.
The mode argument works like the mode argument to toWeek()
. For the single-argument syntax, a mode value of 0 is used.
toISOYear()
is a compatibility function that is equivalent to intDiv(toYearWeek(date,3),100)
.
The week number returned by toYearWeek()
can be different from what the toWeek()
returns. toWeek()
always returns week number in the context of the given year, and in case toWeek()
returns 0
, toYearWeek()
returns the value corresponding to the last week of previous year. See prev_yearWeek
in example below.
Syntax
Alias: YEARWEEK
The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.
Example
toDaysSinceYearZero
Returns for a given date, the number of days passed since 1 January 0000 in the proleptic Gregorian calendar defined by ISO 8601. The calculation is the same as in MySQL's TO_DAYS()
function.
Syntax
Alias: TO_DAYS
Arguments
date
— The date to calculate the number of days passed since year zero from. Date, Date32, DateTime or DateTime64.time_zone
— A String type const value or an expression represent the time zone. String types
Returned value
The number of days passed since date 0000-01-01. UInt32.
Example
Result:
See Also
fromDaysSinceYearZero
Returns for a given number of days passed since 1 January 0000 the corresponding date in the proleptic Gregorian calendar defined by ISO 8601. The calculation is the same as in MySQL's FROM_DAYS()
function.
The result is undefined if it cannot be represented within the bounds of the Date type.
Syntax
Alias: FROM_DAYS
Arguments
days
— The number of days passed since year zero.
Returned value
The date corresponding to the number of days passed since year zero. Date.
Example
Result:
See Also
fromDaysSinceYearZero32
Like fromDaysSinceYearZero but returns a Date32.
age
Returns the unit
component of the difference between startdate
and enddate
. The difference is calculated using a precision of 1 nanosecond.
E.g. the difference between 2021-12-29
and 2022-01-01
is 3 days for day
unit, 0 months for month
unit, 0 years for year
unit.
For an alternative to age
, see function date_diff
.
Syntax
Arguments
-
unit
— The type of interval for result. String. Possible values:nanosecond
,nanoseconds
,ns
microsecond
,microseconds
,us
,u
millisecond
,milliseconds
,ms
second
,seconds
,ss
,s
minute
,minutes
,mi
,n
hour
,hours
,hh
,h
day
,days
,dd
,d
week
,weeks
,wk
,ww
month
,months
,mm
,m
quarter
,quarters
,qq
,q
year
,years
,yyyy
,yy
-
startdate
— The first time value to subtract (the subtrahend). Date, Date32, DateTime or DateTime64. -
enddate
— The second time value to subtract from (the minuend). Date, Date32, DateTime or DateTime64. -
timezone
— Timezone name (optional). If specified, it is applied to bothstartdate
andenddate
. If not specified, timezones ofstartdate
andenddate
are used. If they are not the same, the result is unspecified. String.
Returned value
Difference between enddate
and startdate
expressed in unit
. Int.
Example
Result:
Result:
date_diff
Returns the count of the specified unit
boundaries crossed between the startdate
and the enddate
.
The difference is calculated using relative units, e.g. the difference between 2021-12-29
and 2022-01-01
is 3 days for unit day
(see toRelativeDayNum), 1 month for unit month
(see toRelativeMonthNum) and 1 year for unit year
(see toRelativeYearNum).
If unit week
was specified, date_diff
assumes that weeks start on Monday. Note that this behavior is different from that of function toWeek()
in which weeks start by default on Sunday.
For an alternative to date_diff
, see function age
.
Syntax
Aliases: dateDiff
, DATE_DIFF
, timestampDiff
, timestamp_diff
, TIMESTAMP_DIFF
.
Arguments
-
unit
— The type of interval for result. String. Possible values:nanosecond
,nanoseconds
,ns
microsecond
,microseconds
,us
,u
millisecond
,milliseconds
,ms
second
,seconds
,ss
,s
minute
,minutes
,mi
,n
hour
,hours
,hh
,h
day
,days
,dd
,d
week
,weeks
,wk
,ww
month
,months
,mm
,m
quarter
,quarters
,qq
,q
year
,years
,yyyy
,yy
-
startdate
— The first time value to subtract (the subtrahend). Date, Date32, DateTime or DateTime64. -
enddate
— The second time value to subtract from (the minuend). Date, Date32, DateTime or DateTime64. -
timezone
— Timezone name (optional). If specified, it is applied to bothstartdate
andenddate
. If not specified, timezones ofstartdate
andenddate
are used. If they are not the same, the result is unspecified. String.
Returned value
Difference between enddate
and startdate
expressed in unit
. Int.
Example
Result:
Result:
date_trunc
Truncates date and time data to the specified part of date.
Syntax
Alias: dateTrunc
.
Arguments
-
unit
— The type of interval to truncate the result. String Literal. Possible values:nanosecond
- Compatible only with DateTime64microsecond
- Compatible only with DateTime64milisecond
- Compatible only with DateTime64second
minute
hour
day
week
month
quarter
year
unit
argument is case-insensitive. -
value
— Date and time. Date, Date32, DateTime or DateTime64. -
timezone
— Timezone name for the returned value (optional). If not specified, the function uses the timezone of thevalue
parameter. String.
Returned value
- Value, truncated to the specified part of date. DateTime.
Example
Query without timezone:
Result:
Query with the specified timezone:
Result:
See Also
date_add
Adds the time interval or date interval to the provided date or date with time.
If the addition results in a value outside the bounds of the data type, the result is undefined.
Syntax
Alternative syntax:
Aliases: dateAdd
, DATE_ADD
.
Arguments
-
unit
— The type of interval to add. Note: This is not a String and must therefore not be quoted. Possible values:second
minute
hour
day
week
month
quarter
year
-
value
— Value of interval to add. Int. -
date
— The date or date with time to whichvalue
is added. Date, Date32, DateTime or DateTime64.
Returned value
Date or date with time obtained by adding value
, expressed in unit
, to date
. Date, Date32, DateTime or DateTime64.
Example
Result:
Result:
See Also
date_sub
Subtracts the time interval or date interval from the provided date or date with time.
If the subtraction results in a value outside the bounds of the data type, the result is undefined.
Syntax
Alternative syntax:
Aliases: dateSub
, DATE_SUB
.
Arguments
-
unit
— The type of interval to subtract. Note: This is not a String and must therefore not be quoted.Possible values:
second
minute
hour
day
week
month
quarter
year
-
value
— Value of interval to subtract. Int. -
date
— The date or date with time from whichvalue
is subtracted. Date, Date32, DateTime or DateTime64.
Returned value
Date or date with time obtained by subtracting value
, expressed in unit
, from date
. Date, Date32, DateTime or DateTime64.
Example
Result:
Result:
See Also
timestamp_add
Adds the specified time value with the provided date or date time value.
If the addition results in a value outside the bounds of the data type, the result is undefined.
Syntax
Aliases: timeStampAdd
, TIMESTAMP_ADD
.
Arguments
-
date
— Date or date with time. Date, Date32, DateTime or DateTime64. -
value
— Value of interval to add. Int. -
unit
— The type of interval to add. String. Possible values:second
minute
hour
day
week
month
quarter
year
Returned value
Date or date with time with the specified value
expressed in unit
added to date
. Date, Date32, DateTime or DateTime64.
Example
Result:
timestamp_sub
Subtracts the time interval from the provided date or date with time.
If the subtraction results in a value outside the bounds of the data type, the result is undefined.
Syntax
Aliases: timeStampSub
, TIMESTAMP_SUB
.
Arguments
-
unit
— The type of interval to subtract. String. Possible values:second
minute
hour
day
week
month
quarter
year
-
value
— Value of interval to subtract. Int. -
date
— Date or date with time. Date, Date32, DateTime or DateTime64.
Returned value
Date or date with time obtained by subtracting value
, expressed in unit
, from date
. Date, Date32, DateTime or DateTime64.
Example
Result:
addDate
Adds the time interval to the provided date, date with time or String-encoded date / date with time.
If the addition results in a value outside the bounds of the data type, the result is undefined.
Syntax
Arguments
date
— The date or date with time to whichinterval
is added. Date, Date32, DateTime, DateTime64, or Stringinterval
— Interval to add. Interval.
Returned value
Date or date with time obtained by adding interval
to date
. Date, Date32, DateTime or DateTime64.
Example
Result:
Alias: ADDDATE
See Also
subDate
Subtracts the time interval from the provided date, date with time or String-encoded date / date with time.
If the subtraction results in a value outside the bounds of the data type, the result is undefined.
Syntax
Arguments
date
— The date or date with time from whichinterval
is subtracted. Date, Date32, DateTime, DateTime64, or Stringinterval
— Interval to subtract. Interval.
Returned value
Date or date with time obtained by subtracting interval
from date
. Date, Date32, DateTime or DateTime64.
Example
Result:
Alias: SUBDATE
See Also
now
Returns the current date and time at the moment of query analysis. The function is a constant expression.
Alias: current_timestamp
.
Syntax
Arguments
timezone
— Timezone name for the returned value (optional). String.
Returned value
- Current date and time. DateTime.
Example
Query without timezone:
Result:
Query with the specified timezone:
Result:
now64
Returns the current date and time with sub-second precision at the moment of query analysis. The function is a constant expression.
Syntax
Arguments
scale
- Tick size (precision): 10-precision seconds. Valid range: [ 0 : 9 ]. Typically, are used - 3 (default) (milliseconds), 6 (microseconds), 9 (nanoseconds).timezone
— Timezone name for the returned value (optional). String.
Returned value
- Current date and time with sub-second precision. DateTime64.
Example
Result:
nowInBlock
Returns the current date and time at the moment of processing of each block of data. In contrast to the function now, it is not a constant expression, and the returned value will be different in different blocks for long-running queries.
It makes sense to use this function to generate the current time in long-running INSERT SELECT queries.
Syntax
Arguments
timezone
— Timezone name for the returned value (optional). String.
Returned value
- Current date and time at the moment of processing of each block of data. DateTime.
Example
Result:
today
Returns the current date at moment of query analysis. It is the same as 'toDate(now())' and has aliases: curdate
, current_date
.
Syntax
Arguments
- None
Returned value
- Current date. DateTime.
Example
Query:
Result:
Running the query above on the 3rd of March 2024 would have returned the following response:
yesterday
Accepts zero arguments and returns yesterday's date at one of the moments of query analysis. The same as 'today() - 1'.
timeSlot
Round the time to the start of a half-an-hour length interval.
Syntax
Arguments
time
— Time to round to the start of a half-an-hour length interval. DateTime/Date32/DateTime64.time_zone
— A String type const value or an expression representing the time zone. String.
Though this function can take values of the extended types Date32
and DateTime64
as an argument, passing it a time outside the normal range (year 1970 to 2149 for Date
/ 2106 for DateTime
) will produce wrong results.
Return type
- Returns the time rounded to the start of a half-an-hour length interval. DateTime.
Example
Query:
Result:
toYYYYMM
Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 100 + MM). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.
This function is the opposite of function YYYYMMDDToDate()
.
Example
Result:
toYYYYMMDD
Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 10000 + MM * 100 + DD). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.
Example
Result:
toYYYYMMDDhhmmss
Converts a date or date with time to a UInt64 number containing the year and month number (YYYY * 10000000000 + MM * 100000000 + DD * 1000000 + hh * 10000 + mm * 100 + ss). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.
Example
Result:
YYYYMMDDToDate
Converts a number containing the year, month and day number to a Date.
This function is the opposite of function toYYYYMMDD()
.
The output is undefined if the input does not encode a valid Date value.
Syntax
Arguments
Returned value
- a date created from the arguments. Date.
Example
Result:
YYYYMMDDToDate32
Like function YYYYMMDDToDate()
but produces a Date32.
YYYYMMDDhhmmssToDateTime
Converts a number containing the year, month, day, hours, minute and second number to a DateTime.
The output is undefined if the input does not encode a valid DateTime value.
This function is the opposite of function toYYYYMMDDhhmmss()
.
Syntax
Arguments
yyyymmddhhmmss
- A number representing the year, month and day. Integer, Float or Decimal.timezone
- Timezone for the returned value (optional).
Returned value
- a date with time created from the arguments. DateTime.
Example
Result:
YYYYMMDDhhmmssToDateTime64
Like function YYYYMMDDhhmmssToDate()
but produces a DateTime64.
Accepts an additional, optional precision
parameter after the timezone
parameter.
changeYear
Changes the year component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the year. Integer.
Returned value
- The same type as
date_or_datetime
.
Example
Result:
changeMonth
Changes the month component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the month. Integer.
Returned value
- Returns a value of same type as
date_or_datetime
.
Example
Result:
changeDay
Changes the day component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the day. Integer.
Returned value
- Returns a value of same type as
date_or_datetime
.
Example
Result:
changeHour
Changes the hour component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the hour. Integer.
Returned value
- Returns a value of same type as
date_or_datetime
. If the input is a Date, return DateTime. If the input is a Date32, return DateTime64.
Example
Result:
changeMinute
Changes the minute component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the minute. Integer.
Returned value
- Returns a value of same type as
date_or_datetime
. If the input is a Date, return DateTime. If the input is a Date32, return DateTime64.
Example
Result:
changeSecond
Changes the second component of a date or date time.
Syntax
Arguments
date_or_datetime
- a Date, Date32, DateTime or DateTime64value
- a new value of the second. Integer.
Returned value
- Returns a value of same type as
date_or_datetime
. If the input is a Date, return DateTime. If the input is a Date32, return DateTime64.
Example
Result:
addYears
Adds a specified number of years to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of years to. Date/Date32/DateTime/DateTime64, String.num
: Number of years to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
years. Date/Date32/DateTime/DateTime64.
Example
addQuarters
Adds a specified number of quarters to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of quarters to. Date/Date32/DateTime/DateTime64, String.num
: Number of quarters to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
quarters. Date/Date32/DateTime/DateTime64.
Example
addMonths
Adds a specified number of months to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of months to. Date/Date32/DateTime/DateTime64, String.num
: Number of months to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
months. Date/Date32/DateTime/DateTime64.
Example
addWeeks
Adds a specified number of weeks to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of weeks to. Date/Date32/DateTime/DateTime64, String.num
: Number of weeks to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
weeks. Date/Date32/DateTime/DateTime64.
Example
addDays
Adds a specified number of days to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of days to. Date/Date32/DateTime/DateTime64, String.num
: Number of days to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
days. Date/Date32/DateTime/DateTime64.
Example
addHours
Adds a specified number of days to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of hours to. Date/Date32/DateTime/DateTime64, String.num
: Number of hours to add. (U)Int*, Float*.
Returned value o
- Returns
date
plusnum
hours. Date/Date32/DateTime/DateTime64.
Example
addMinutes
Adds a specified number of minutes to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of minutes to. Date/Date32/DateTime/DateTime64, String.num
: Number of minutes to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
minutes. Date/Date32/DateTime/DateTime64.
Example
addSeconds
Adds a specified number of seconds to a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to add specified number of seconds to. Date/Date32/DateTime/DateTime64, String.num
: Number of seconds to add. (U)Int*, Float*.
Returned value
- Returns
date
plusnum
seconds. Date/Date32/DateTime/DateTime64.
Example
addMilliseconds
Adds a specified number of milliseconds to a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to add specified number of milliseconds to. DateTime/DateTime64, String.num
: Number of milliseconds to add. (U)Int*, Float*.
Returned value
- Returns
date_time
plusnum
milliseconds. DateTime64.
Example
addMicroseconds
Adds a specified number of microseconds to a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to add specified number of microseconds to. DateTime/DateTime64, String.num
: Number of microseconds to add. (U)Int*, Float*.
Returned value
- Returns
date_time
plusnum
microseconds. DateTime64.
Example
addNanoseconds
Adds a specified number of microseconds to a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to add specified number of nanoseconds to. DateTime/DateTime64, String.num
: Number of nanoseconds to add. (U)Int*, Float*.
Returned value
- Returns
date_time
plusnum
nanoseconds. DateTime64.
Example
addInterval
Adds an interval to another interval or tuple of intervals.
Syntax
Parameters
interval_1
: First interval or tuple of intervals. interval, tuple(interval).interval_2
: Second interval to be added. interval.
Returned value
Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(1)
and toIntervalDay(2)
are passed then the result will be (3)
rather than (1,1)
.
Example
Query:
Result:
addTupleOfIntervals
Consecutively adds a tuple of intervals to a Date or a DateTime.
Syntax
Parameters
date
: First interval or interval of tuples. date/date32/datetime/datetime64.intervals
: Tuple of intervals to add todate
. tuple(interval).
Returned value
- Returns
date
with addedintervals
. date/date32/datetime/datetime64.
Example
Query:
Result:
subtractYears
Subtracts a specified number of years from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of years from. Date/Date32/DateTime/DateTime64, String.num
: Number of years to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
years. Date/Date32/DateTime/DateTime64.
Example
subtractQuarters
Subtracts a specified number of quarters from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of quarters from. Date/Date32/DateTime/DateTime64, String.num
: Number of quarters to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
quarters. Date/Date32/DateTime/DateTime64.
Example
subtractMonths
Subtracts a specified number of months from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of months from. Date/Date32/DateTime/DateTime64, String.num
: Number of months to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
months. Date/Date32/DateTime/DateTime64.
Example
subtractWeeks
Subtracts a specified number of weeks from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of weeks from. Date/Date32/DateTime/DateTime64, String.num
: Number of weeks to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
weeks. Date/Date32/DateTime/DateTime64.
Example
subtractDays
Subtracts a specified number of days from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of days from. Date/Date32/DateTime/DateTime64, String.num
: Number of days to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
days. Date/Date32/DateTime/DateTime64.
Example
subtractHours
Subtracts a specified number of hours from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of hours from. Date/Date32/Datetime/Datetime64, String.num
: Number of hours to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
hours. Date/Date32/Datetime/DateTime64.
Example
subtractMinutes
Subtracts a specified number of minutes from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of minutes from. Date/Date32/DateTime/DateTime64, String.num
: Number of minutes to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
minutes. Date/Date32/DateTime/DateTime64.
Example
subtractSeconds
Subtracts a specified number of seconds from a date, a date with time or a string-encoded date / date with time.
Syntax
Parameters
date
: Date / date with time to subtract specified number of seconds from. Date/Date32/DateTime/DateTime64, String.num
: Number of seconds to subtract. (U)Int*, Float*.
Returned value
- Returns
date
minusnum
seconds. Date/Date32/DateTime/DateTime64.
Example
subtractMilliseconds
Subtracts a specified number of milliseconds from a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to subtract specified number of milliseconds from. DateTime/DateTime64, String.num
: Number of milliseconds to subtract. (U)Int*, Float*.
Returned value
- Returns
date_time
minusnum
milliseconds. DateTime64.
Example
subtractMicroseconds
Subtracts a specified number of microseconds from a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to subtract specified number of microseconds from. DateTime/DateTime64, String.num
: Number of microseconds to subtract. (U)Int*, Float*.
Returned value
- Returns
date_time
minusnum
microseconds. DateTime64.
Example
subtractNanoseconds
Subtracts a specified number of nanoseconds from a date with time or a string-encoded date with time.
Syntax
Parameters
date_time
: Date with time to subtract specified number of nanoseconds from. DateTime/DateTime64, String.num
: Number of nanoseconds to subtract. (U)Int*, Float*.
Returned value
- Returns
date_time
minusnum
nanoseconds. DateTime64.
Example
subtractInterval
Adds a negated interval to another interval or tuple of intervals.
Syntax
Parameters
interval_1
: First interval or interval of tuples. interval, tuple(interval).interval_2
: Second interval to be negated. interval.
Returned value
Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(2)
and toIntervalDay(1)
are passed then the result will be (1)
rather than (2,1)
Example
Query:
Result:
subtractTupleOfIntervals
Consecutively subtracts a tuple of intervals from a Date or a DateTime.
Syntax
Parameters
date
: First interval or interval of tuples. Date/Date32/DateTime/DateTime64.intervals
: Tuple of intervals to subtract fromdate
. tuple(interval).
Returned value
- Returns
date
with subtractedintervals
. Date/Date32/DateTime/DateTime64.
Example
Query:
Result:
timeSlots
For a time interval starting at 'StartTime' and continuing for 'Duration' seconds, it returns an array of moments in time, consisting of points from this interval rounded down to the 'Size' in seconds. 'Size' is an optional parameter set to 1800 (30 minutes) by default.
This is necessary, for example, when searching for pageviews in the corresponding session.
Accepts DateTime and DateTime64 as 'StartTime' argument. For DateTime, 'Duration’ and ’Size’ arguments must be UInt32
. For ’DateTime64’ they must be Decimal64
.
Returns an array of DateTime/DateTime64 (return type matches the type of ’StartTime’). For DateTime64, the return value's scale can differ from the scale of ’StartTime’ --- the highest scale among all given arguments is taken.
Syntax
Example
Result:
formatDateTime
Formats a Time according to the given Format string. Format is a constant expression, so you cannot have multiple formats for a single result column.
formatDateTime uses MySQL datetime format style, refer to https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_date-format.
The opposite operation of this function is parseDateTime.
Alias: DATE_FORMAT
.
Syntax
Returned value(s)
Returns time and date values according to the determined format.
Replacement fields
Using replacement fields, you can define a pattern for the resulting string. "Example" column shows formatting result for 2018-01-02 22:33:44
.
Placeholder | Description | Example |
---|---|---|
%a | abbreviated weekday name (Mon-Sun) | Mon |
%b | abbreviated month name (Jan-Dec) | Jan |
%c | month as an integer number (01-12), see 'Note 4' below | 01 |
%C | year divided by 100 and truncated to integer (00-99) | 20 |
%d | day of the month, zero-padded (01-31) | 02 |
%D | Short MM/DD/YY date, equivalent to %m/%d/%y | 01/02/18 |
%e | day of the month, space-padded (1-31) | 2 |
%f | fractional second, see 'Note 1' and 'Note 2' below | 123456 |
%F | short YYYY-MM-DD date, equivalent to %Y-%m-%d | 2018-01-02 |
%g | two-digit year format, aligned to ISO 8601, abbreviated from four-digit notation | 18 |
%G | four-digit year format for ISO week number, calculated from the week-based year defined by the ISO 8601 standard, normally useful only with %V | 2018 |
%h | hour in 12h format (01-12) | 09 |
%H | hour in 24h format (00-23) | 22 |
%i | minute (00-59) | 33 |
%I | hour in 12h format (01-12) | 10 |
%j | day of the year (001-366) | 002 |
%k | hour in 24h format (00-23), see 'Note 4' below | 14 |
%l | hour in 12h format (01-12), see 'Note 4' below | 09 |
%m | month as an integer number (01-12) | 01 |
%M | full month name (January-December), see 'Note 3' below | January |
%n | new-line character ('’) | |
%p | AM or PM designation | PM |
%Q | Quarter (1-4) | 1 |
%r | 12-hour HH:MM AM/PM time, equivalent to %h:%i %p | 10:30 PM |
%R | 24-hour HH:MM time, equivalent to %H:%i | 22:33 |
%s | second (00-59) | 44 |
%S | second (00-59) | 44 |
%t | horizontal-tab character (’) | |
%T | ISO 8601 time format (HH:MM:SS), equivalent to %H:%i:%S | 22:33:44 |
%u | ISO 8601 weekday as number with Monday as 1 (1-7) | 2 |
%V | ISO 8601 week number (01-53) | 01 |
%w | weekday as a integer number with Sunday as 0 (0-6) | 2 |
%W | full weekday name (Monday-Sunday) | Monday |
%y | Year, last two digits (00-99) | 18 |
%Y | Year | 2018 |
%z | Time offset from UTC as +HHMM or -HHMM | -0500 |
%% | a % sign | % |
Note 1: In ClickHouse versions earlier than v23.4, %f
prints a single zero (0) if the formatted value is a Date, Date32 or DateTime (which have no fractional seconds) or a DateTime64 with a precision of 0. The previous behavior can be restored using setting formatdatetime_f_prints_single_zero = 1
.
Note 2: In ClickHouse versions earlier than v25.1, %f
prints as many digits as specified by the scale of the DateTime64 instead of fixed 6 digits. The previous behavior can be restored using setting formatdatetime_f_prints_scale_number_of_digits= 1
.
Note 3: In ClickHouse versions earlier than v23.4, %M
prints the minute (00-59) instead of the full month name (January-December). The previous behavior can be restored using setting formatdatetime_parsedatetime_m_is_month_name = 0
.
Note 4: In ClickHouse versions earlier than v23.11, function parseDateTime()
required leading zeros for formatters %c
(month) and %l
/%k
(hour), e.g. 07
. In later versions, the leading zero may be omitted, e.g. 7
. The previous behavior can be restored using setting parsedatetime_parse_without_leading_zeros = 0
. Note that function formatDateTime()
by default still prints leading zeros for %c
and %l
/%k
to not break existing use cases. This behavior can be changed by setting formatdatetime_format_without_leading_zeros = 1
.
Example
Result:
Result:
Additionally, the formatDateTime
function can take a third String argument containing the name of the time zone. Example: Asia/Istanbul
. In this case, the time is formatted according to the specified time zone.
Example
See Also
formatDateTimeInJodaSyntax
Similar to formatDateTime, except that it formats datetime in Joda style instead of MySQL style. Refer to https://joda-time.sourceforge.net/apidocs/org/joda/time/format/DateTimeFormat.html.
The opposite operation of this function is parseDateTimeInJodaSyntax.
Replacement fields
Using replacement fields, you can define a pattern for the resulting string.
Placeholder | Description | Presentation | Examples |
---|---|---|---|
G | era | text | AD |
C | century of era (>=0) | number | 20 |
Y | year of era (>=0) | year | 1996 |
x | weekyear (not supported yet) | year | 1996 |
w | week of weekyear (not supported yet) | number | 27 |
e | day of week | number | 2 |
E | day of week | text | Tuesday; Tue |
y | year | year | 1996 |
D | day of year | number | 189 |
M | month of year | month | July; Jul; 07 |
d | day of month | number | 10 |
a | halfday of day | text | PM |
K | hour of halfday (0~11) | number | 0 |
h | clockhour of halfday (1~12) | number | 12 |
H | hour of day (0~23) | number | 0 |
k | clockhour of day (1~24) | number | 24 |
m | minute of hour | number | 30 |
s | second of minute | number | 55 |
S | fraction of second | number | 978 |
z | time zone | text | Eastern Standard Time; EST |
Z | time zone offset | zone | -0800; -0812 |
' | escape for text | delimiter | |
'' | single quote | literal | ' |
Example
Result:
dateName
Returns specified part of date.
Syntax
Arguments
date_part
— Date part. Possible values: 'year', 'quarter', 'month', 'week', 'dayofyear', 'day', 'weekday', 'hour', 'minute', 'second'. String.date
— Date. Date, Date32, DateTime or DateTime64.timezone
— Timezone. Optional. String.
Returned value
- The specified part of date. String
Example
Result:
monthName
Returns name of the month.
Syntax
Arguments
date
— Date or date with time. Date, DateTime or DateTime64.
Returned value
- The name of the month. String
Example
Result:
fromUnixTimestamp
This function converts a Unix timestamp to a calendar date and a time of a day.
It can be called in two ways:
When given a single argument of type Integer, it returns a value of type DateTime, i.e. behaves like toDateTime.
Alias: FROM_UNIXTIME
.
Example:
Result:
When given two or three arguments where the first argument is a value of type Integer, Date, Date32, DateTime or DateTime64, the second argument is a constant format string and the third argument is an optional constant time zone string, the function returns a value of type String, i.e. it behaves like formatDateTime. In this case, MySQL's datetime format style is used.
Example:
Result:
See Also
fromUnixTimestampInJodaSyntax
Same as fromUnixTimestamp but when called in the second way (two or three arguments), the formatting is performed using Joda style instead of MySQL style.
Example:
Result:
toModifiedJulianDay
Converts a Proleptic Gregorian calendar date in text form YYYY-MM-DD
to a Modified Julian Day number in Int32. This function supports date from 0000-01-01
to 9999-12-31
. It raises an exception if the argument cannot be parsed as a date, or the date is invalid.
Syntax
Arguments
date
— Date in text form. String or FixedString.
Returned value
- Modified Julian Day number. Int32.
Example
Result:
toModifiedJulianDayOrNull
Similar to toModifiedJulianDay(), but instead of raising exceptions it returns NULL
.
Syntax
Arguments
date
— Date in text form. String or FixedString.
Returned value
- Modified Julian Day number. Nullable(Int32).
Example
Result:
fromModifiedJulianDay
Converts a Modified Julian Day number to a Proleptic Gregorian calendar date in text form YYYY-MM-DD
. This function supports day number from -678941
to 2973483
(which represent 0000-01-01 and 9999-12-31 respectively). It raises an exception if the day number is outside of the supported range.
Syntax
Arguments
day
— Modified Julian Day number. Any integral types.
Returned value
- Date in text form. String
Example
Result:
fromModifiedJulianDayOrNull
Similar to fromModifiedJulianDayOrNull(), but instead of raising exceptions it returns NULL
.
Syntax
Arguments
day
— Modified Julian Day number. Any integral types.
Returned value
- Date in text form. Nullable(String)
Example
Result:
toUTCTimestamp
Convert DateTime/DateTime64 type value from other time zone to UTC timezone timestamp. This function is mainly included for compatibility with Apache Spark and similar frameworks.
Syntax
Arguments
time_val
— A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 typestime_zone
— A String type const value or an expression represent the time zone. String types
Returned value
- DateTime/DateTime64 in text form
Example
Result:
fromUTCTimestamp
Convert DateTime/DateTime64 type value from UTC timezone to other time zone timestamp. This function is mainly included for compatibility with Apache Spark and similar frameworks.
Syntax
Arguments
time_val
— A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 typestime_zone
— A String type const value or an expression represent the time zone. String types
Returned value
- DateTime/DateTime64 in text form
Example
Result:
UTCTimestamp
Returns the current date and time at the moment of query analysis. The function is a constant expression.
This function gives the same result that now('UTC')
would. It was added only for MySQL support and now
is the preferred usage.
Syntax
Alias: UTC_timestamp
.
Returned value
- Returns the current date and time at the moment of query analysis. DateTime.
Example
Query:
Result:
timeDiff
Returns the difference between two dates or dates with time values. The difference is calculated in units of seconds. It is same as dateDiff
and was added only for MySQL support. dateDiff
is preferred.
Syntax
Arguments*
first_datetime
— A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 typessecond_datetime
— A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 types
Returned value
The difference between two dates or dates with time values in seconds.
Example
Query:
Result: