Date Functions

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    N1QL date functions return the system clock value or manipulate the datetime values, which are represented as a string or an integer. These functions are very useful for manipulating dates in datasets with various date formats and timezones.

    Timezones

    Datetime values are always tied to a specific timezone, either explicitly in the date value, or implicitly in the application. The date functions in N1QL therefore support multiple different timezones.

    UTC

    UTC, The Coordinated Universal Time is the primary time standard by which the world regulates clocks and time. It is defined as the time at 0° longitude and is consistent, as it does not take into account daylight savings time. You can read further about UTC at https://www.timeanddate.com/time/aboututc.html.

    All N1QL functions which accept a timezone as an argument also accept UTC.

    IANA Timezones

    Many applications operate across multiple different time zones and may not necessarily use UTC. Therefore, it is important for the database to be able to handle and manipulate dates in these time zones in a consistent manner. Many date functions take the time zone as an additional argument.

    Timezones are case sensitive, Europe/London is not the same as europe/london.

    It is important to note that many time zones change their UTC offset based on daylight savings time, as a result the UTC offset of times may change based on the time of year. N1QL take this into account when converting dates.

    Below are a few examples of commonly used timezones and their offsets:

    Table 1. Common Timezones
    Timezone UTC Offset (without daylight savings time) UTC Offset (during daylight savings time)

    America/New_York

    -05:00

    -04:00

    America/Tijuana

    -08:00

    -07:00

    Europe/Paris

    +01:00

    +02:00

    Europe/London

    +00:00

    +01:00

    Asia/Tel_Aviv

    +02:00

    +03:00

    Asia/Kolkata

    +05:30

    +05:30

    Local System Timezone

    Many functions default to using the local timezone of the system, which will be one of the IANA timezones.

    Date Formats

    N1QL date functions accept dates in either Epoch/UNIX timestamp format or string date format. N1QL is then able to represent the passed date as a standardized date object internally. In general, functions whose name contains the word STR are designed to use string formats while MILLIS functions are designed to use Epoch/UNIX timestamps.

    Epoch/UNIX Timestamps

    Epoch/UNIX time is the number of seconds (or milliseconds) that have elapsed since 1970-01-01T00:00:00.000Z (Thursday, 1 January 1970 at midnight), not including leap seconds. This can be useful for numeric and timezone agnostic representations of dates. While Epoch/UNIX time can be represented in either seconds or milliseconds, all N1QL date functions specifically treat Epoch/UNIX timestamps as milliseconds. For example, the date 2017-01-31T10:02:07Z would equate to an Epoch/UNIX timestamp of 1485856927000.

    Date String Formats

    In many cases, dates are not stored as Epoch/UNIX timestamp but instead as more human-readable formats, such as 2006-01-02T15:04:05.567+08:00. Therefore, N1QL also provides convenience methods to allow you to manipulate and convert dates in string format.

    N1QL accepts format strings following several conventions:

    • ISO-8601 example dates, e.g. 1111-11-11.

    • Date string component codes, e.g. YYYY-MM-DD.

    • Go language native dates, e.g. specifically 2006-01-02 for year, month, and day.

    • Percent-style date format specifiers, e.g. %Y-%m-%d.

    Only a single style can be used at a time in a specified format string.

    • ISO-8601 Dates

    • Date String Codes

    • Go Reference Dates

    • Percent-Style Dates

    ISO-8601 example dates are composed of the following date components.

    Component Code Value

    Year

    YYYY

    Any four-digit integer from 1111 to 9999

    Month (of the year)

    MM

    Any two digit integer from 01 to 12

    Day (of the month)

    DD

    Any two digit integer from 01 to 31

    Hour (of the day)

    hh

    Any two-digit integer from 00 to 23

    Minute (of the hour)

    mm

    Any two-digit integer from 00 to 59

    Second (of the minute)

    ss

    Any two-digit integer from 00 to 59

    Millisecond (of the second) — output only

    s

    Any three-digit integer from 000 to 999

    Time Zone (as UTC offset)

    TZD

    UTC offset in the format ±hh:mm

    A UTC offset of 0 (+00:00) can just be specified as Z.

    To specify a date format, you must put together example component values, as specified above, to create one of the following date formats. ISO-8601 date formats are very specific; they must contain the correct components in the correct order, with punctuation exactly as shown.

    Format Example

    YYYY-MM-DDThh:mm:ss.sTZD

    1111-12-31T23:00:59.999+00:00 or 1111-12-31T23:00:59.999Z

    YYYY-MM-DDThh:mm:ssTZD

    1111-12-31T23:00:59+00:00 or 1111-12-31T23:00:59Z

    YYYY-MM-DDThh:mm:ss.s

    1111-12-31T23:00:59.999

    YYYY-MM-DDThh:mm:ss

    1111-12-31T23:00:59

    YYYY-MM-DD hh:mm:ss.sTZD

    1111-12-31 23:00:59.999+00:00 or 1111-12-31 23:00:59.999Z

    YYYY-MM-DD hh:mm:ssTZD

    1111-12-31 23:00:59+00:00 or 1111-12-31 23:00:59Z

    YYYY-MM-DD hh:mm:ss.s

    1111-12-31 23:00:59.999

    YYYY-MM-DD hh:mm:ss

    1111-12-31 23:00:59

    YYYY-MM-DD

    1111-12-31

    hh:mm:ss.sTZD

    23:00:59.999+00:00 or 23:00:59.999Z

    hh:mm:ssTZD

    23:00:59+00:00 or 23:00:59Z

    hh:mm:ss.s

    23:00:59.999

    hh:mm:ss

    23:00:59

    The examples above use arbitrary values for the date components. You can use any valid values in your date components, as long as the date format contains the correct combination of components and punctuation.

    Note, however, that if you use Go reference date values as the date components, the example date is interpreted as a Go reference date, rather than an ISO-8601 example date. This may cause some date formats to be interpreted differently to what you expect. For example, the date format 2006-02-01 is interpreted as a Go reference date, where 02 is the day and 01 is the month.

    For greater flexibility, you can specify a date format using date string codes. These are based on the alphabetic format codes from the ISO-8601 standard, with some extensions. The date string codes are given below.

    Code Component

    CC

    2-digit century

    YYYY

    4-digit century and year

    YY

    2-digit year [note]

    MM

    2-digit month

    DD

    2-digit day

    hh

    2-digit hour, 00-23

    HH

    2-digit hour, 00-23

    mm

    2-digit minute, 00-59

    ss

    2-digit second, 00-59

    s

    Fraction of a second (down to millisecond) — output only

    TZD

    Time Zone (as UTC offset)

    To specify a date format, you can put the date string components together in any order, along with any other characters as required.

    Characters which are not part of the format specification are matched literally and produced unaltered, with the exception of Unicode U+0020, i.e. space " ", which matches any single character when parsing, and is produced unaltered on output. For example, YYYY MM DD parses 2021-06-28, 2021/06/28, 2021.06.28, etc.

    You can specify a date format using Go language date components. The available reference date components are given below.

    Component Reference Date Meaning

    Year

    2006

    4-digit century and year

    06

    2-digit year [note]

    Month

    1

    Unpadded month

    01

    Zero-padded 2-digit month

    January

    Full English month name

    Jan

    Abbreviated English month name

    Day

    2

    Unpadded day of the month

    _2

    Space-padded 2-digit day of the month

    02

    Zero-padded 2-digit day of the month

    Monday

    Full English day name

    Mon

    Abbreviated English day name

    __2

    Space-padded 3-digit day of the year

    002

    Zero-padded 3-digit day of the year

    Hour

    3

    Unpadded hour, 1-12

    03

    Zero-padded 2-digit hour, 01-12

    15

    Zero-padded 2-digit hour, 00-23

    AM or PM

    PM

    AM or PM (upper case)

    pm

    am or pm (lower case)

    Minute

    4

    Unpadded minute, 0-59

    04

    Zero-padded minute, 00-59

    Second

    5

    Unpadded second, 0-59

    05

    Zero-padded second, 00-59

    Fraction of a second

    ,000 (one or
    .000 more zeros)

    Fraction of a second, to the given number of decimal places

    ,999 (one or
    .999 more nines)

    Fraction of a second, to the given number of decimal places, with trailing zeros removed

    Time zone

    -07
    -0700
    -07:00

    Time Zone (as UTC offset)

    Z07
    Z0700
    Z07:00

    Time Zone (as UTC offset);
    a UTC offset of 0 (+00:00) is output as Z

    To specify a date format, you can put the reference date components together in any order, along with any other characters as required.

    Characters which are not part of the format specification are matched literally and produced unaltered, with the exception of Unicode U+0020, i.e. space " ", which matches any single character when parsing, and is produced unaltered on output. For example, 2006 01 02 parses 2021-06-28, 2021/06/28, 2021.06.28, etc.

    Date and time functions also accept printf-style format specifiers for date formats, based on the Unix date command. Format specifiers begin with a percent character % and take the following form:

    format-specifier ::= '%' ( '%' | ( '-' | '_' | '0' | '^' )? width? element)
    Syntax diagram: refer to source code listing

    The optional hyphen (-), underscore (_), or zero (0) characters specify the padding for number fields.

    hyphen -

    No padding for numeric date components.

    underscore _

    Padding with spaces for numeric date components.

    zero 0

    Padding with zeros for numeric date components — the default.

    The optional circumflex (^) character specifies case insensitivity when parsing text date components, or a preference for upper case when outputting text date components.

    The width is accepted but ignored for parsing, and is used for output. However, it should rarely be needed, as elements have common or expected default widths.

    The element is a single character which specifies a date component or an entire date format. The elements are given in the table below.

    Element Meaning Example

    D

    Short form date, YYYY-MM-DD

    2021-06-28

    F

    Long form date, YYYY-MM-DDThh:mm:ss.sTZD

    2021-06-28T19:22:59.123+01:00

    Y

    4-digit century and year

    2021

    C

    2-digit century

    20

    y

    2-digit year [note]

    21

    m

    2-digit month

    01

    B

    Full English month name

    January

    b

    Abbreviated English month name

    Jan

    d

    2-digit day

    28

    A

    Full English day name

    Monday

    a

    Abbreviated English day name

    Mon

    f

    English ordinal number suffix

    st (as in 1st)

    H

    2-digit hour, 00-23

    19

    I

    2-digit hour, 01-12

    07

    p

    AM or PM (upper case)

    PM

    P

    am or pm (lower case)

    pm

    M

    2-digit minute, 00-59

    22

    S

    2-digit second, 00-59

    59

    R

    24-hour hour and minute (same as %H:%M)

    19:22

    T

    24-hour time (same as %H:%M:%S)

    19:22:59

    N

    Fraction of a second (down to nanosecond)

    123

    z

    When parsing, matches a time zone in any supported format — ±hh, ±hhmm, ±hh:mm, zone name

    +01
    +0100
    +01:00
    Europe/Paris

    For output, produces time zone in ±hh:mm format

    +01:00

    Z

    When parsing, matches a time zone in any supported format — ±hh, ±hhmm, ±hh:mm, zone name

    +01
    +0100
    +01:00
    Europe/Paris

    For output, produces time zone name

    Europe/Paris

    s

    Seconds since 1970-01-01 00:00:00 UTC

    1624904579

    To specify a date format, you can put the format specifiers together in any order, along with any other characters as required. If you need to include a literal percent symbol in the date format, use the special format specifier %%.

    Characters which are not part of the format specification are matched literally and produced unaltered, with the exception of Unicode U+0020, i.e. space " ", which matches any single character when parsing, and is produced unaltered on output. For example, %Y %m %d parses 2021-06-28, 2021/06/28, 2021.06.28, and so on.

    Default Values

    If the date string does not explicitly declare the value of a component, then the following default values are assumed:

    • The month and day default to 1.

    • The century (when not specified by year) defaults to 19 if year is greater than or equal to 69, or 20 otherwise.

    • All other numeric components default to 0.

    • The time zone defaults to the local local system time zone.

    In cases where the timezone is not specified, the local system time is assumed.

    For example, 2016-02-07 is equivalent to 2016-02-07T00:00:00 and parsing just 16 as the year is equivalent to 2016-01-01T00:00:00 in the local system time zone.

    Manipulating Date Components

    Dates are composed of multiple different components such as the day, year, month, etc. It is important for applications to be able to extract and manipulate particular components of a date, so that these can be used in N1QL queries. Functions such as DATE_ADD_STR() accept a part argument, which is the component to adjust.

    The following are the supported date parts that can be passed to date manipulation functions. These date parts are expressed as strings and are not case-sensitive, so year is regarded the same as YeAr. For all examples, the date being used is 2006-01-02T15:04:05.999Z.

    Table 2. Date and Time Components
    Component Description Lower Bound Upper Bound Example

    millennium

    The millennium (1000 year period), counting from the start of year 0, which is equivalent to 1 BCE.

    -

    -

    3

    century

    The century (100 year period), counting from the start of year 0, which is equivalent to 1 BCE.

    -

    -

    21

    decade

    The decade (10 year period), counting from the start of year 0, which is equivalent to 1 BCE. This is calculated as floor(year / 10).

    -

    -

    200

    year

    The proleptic Gregorian year. The year 0 is equivalent to 1 BCE.

    -

    -

    2006

    iso_year

    The ISO-8601 year. Each ISO-8601 year begins with the Monday of the week containing the 4th of January, so in early January and late December the ISO year may differ from the Gregorian year. Should be used in conjunction with iso_week to get consistent results.

    -

    -

    2006

    quarter

    The number of the quarter (3 month period) of the year. January-March (inclusive) is 1 while October-December (inclusive) is 4.

    1

    4

    1

    month

    The number of the month of the year. January is 1 and December is 12.

    1

    12

    1

    week

    The number of the week of the year. This is the ceiling value of the day of the year divided by 7.

    1

    53

    1

    iso_week

    The number of the week of the year, based on the ISO definition. ISO weeks start on Mondays and the first week of a year contains January 4 of that year. In other words, the first Thursday of a year will always be in week 1 of that year. This results in some different results between week and iso_week, based on the input date.

    For example the iso_week of 2006-01-08T15:04:05.999Z is 1, while the week is 2. Should be used in conjunction with iso_year to get consistent results.

    1

    53

    1

    day

    The day of the month.

    1

    31

    2

    day_of_year or doy

    The day of the year.

    1

    366

    2

    day_of_week or dow

    The day of the week.

    0

    6

    1

    hour

    The hour of the day.

    0

    23

    5

    minute

    The minute of the hour.

    0

    59

    4

    second

    The second of the minute.

    0

    59

    5

    millisecond

    The millisecond of the second.

    0

    999

    999

    timezone

    The offset from UTC in seconds.

    -43200

    43200

    0

    timezone_hour

    The hour component of the offset from UTC.

    -12

    12

    0

    timezone_minute

    The minute component of the offset from UTC.

    -59

    59

    0

    Date Functions

    Below is a list of all date functions that N1QL provides.

    Many date functions use the local system clock value and timezone of the query node to generate results. Therefore, if all nodes running the query service do not have their time appropriately synchronized then you may experience inconsistent behavior. It is recommended that all Couchbase Server nodes have their time synchronized via NTP.
    If any arguments to any of the following functions are MISSING then the result is also MISSING (i.e. no result is returned). Similarly, if any of the arguments are NULL then NULL is returned.

    CLOCK_LOCAL([fmt])

    Description

    The current time (at function evaluation time) of the machine that the query service is running on, in the specified string format.

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified representing the local system time.

    Limitations

    CLOCK_LOCAL() cannot be used as part of an index definition, this includes the indexed fields and the WHERE clause of the index.

    If this function is called multiple times within the same query then the values returned may differ, particularly if the query takes a long time to run. To avoid inconsistencies between multiple calls to CLOCK_LOCAL() within a single query, use NOW_LOCAL() instead.

    Examples

    SELECT CLOCK_LOCAL() as full_date,
           CLOCK_LOCAL('invalid date') as invalid_date,
           CLOCK_LOCAL('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2018-01-23T13:57:29.847-08:00",
        "invalid_date": "2018-01-23T13:57:29.847-08:00",
        "short_date": "2018-01-23"
      }
    ]

    CLOCK_MILLIS()

    Description

    The current time as an Epoch/UNIX timestamp. Its fractional part represents nanoseconds, but the additional precision beyond milliseconds may not be consistent or guaranteed on all platforms.

    Arguments

    This function accepts no arguments.

    Return Value

    A single float value (with 3 decimal places) representing the system time as Epoch/UNIX time.

    Limitations

    CLOCK_MILLIS() cannot be used as part of an index definition, this includes the indexed fields and the WHERE clause of the index.

    If this function is called multiple times within the same query then the values returned may differ, particularly if the query takes a long time to run. To avoid inconsistencies between multiple calls to CLOCK_MILLIS() within a single query, use NOW_MILLIS() instead.

    Examples

    SELECT CLOCK_MILLIS() AS CurrentTime;
    Results
    [
      {
        "CurrentTime": 1516744600430.677
      }
    ]

    CLOCK_STR([fmt])

    Description

    The current time (at function evaluation time) of the machine that the query service is running on, in the specified string format.

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as. .

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified representing the system time.

    Limitations

    CLOCK_STR() cannot be used as part of an index definition, this includes the indexed fields and the WHERE clause of the index.

    If this function is called multiple times within the same query then the values returned may differ, particularly if the query takes a long time to run. To avoid inconsistencies between multiple calls to CLOCK_STR() within a single query, use NOW_STR() instead.

    Examples

    SELECT CLOCK_STR() as full_date,
           CLOCK_STR('invalid date') as invalid_date,
           CLOCK_STR('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2018-01-23T13:55:10.798-08:00",
        "invalid_date": "2018-01-23T13:55:10.798-08:00",
        "short_date": "2018-01-23"
      }
    ]

    CLOCK_TZ(tz [, fmt])

    Description

    The current time (at function evaluation time) in the timezone given by the timezone argument passed to the function. This time is the local system time converted to the specified timezone.

    Arguments

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to convert the local time to.

    If this argument is not a valid timezone then null is returned as the result.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    An date string in the format specified representing the system time in the specified timezone.

    Limitations

    As this function converts the local time, it may not accurately represent the true time in that timezone.

    CLOCK_TZ() cannot be used as part of an index definition, this includes the indexed fields and the WHERE clause of the index.

    If this function is called multiple times within the same query then the values returned may differ, particularly if the query takes a long time to run. To avoid inconsistencies between multiple calls to CLOCK_TZ() within a single query, use NOW_TZ() instead.

    Examples

    SELECT CLOCK_TZ('UTC') as UTC_full_date,
           CLOCK_TZ('UTC', '1111-11-11') as UTC_short_date,
           CLOCK_TZ('invalid timezone') as invalid_timezone,
           CLOCK_TZ('US/Eastern') as us_east,
           CLOCK_TZ('US/Pacific') as us_west;
    Results
    [
      {
        "UTC_full_date": "2018-01-23T21:54:37.178Z",
        "UTC_short_date": "2018-01-23",
        "invalid_timezone": null,
        "us_east": "2018-01-23T16:54:37.18-05:00",
        "us_west": "2018-01-23T13:54:37.181-08:00"
      }
    ]

    CLOCK_UTC([fmt])

    Description

    The current time in UTC. This time is the local system time converted to UTC. This function is provided for convenience and is the same as CLOCK_TZ('UTC').

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    An date string in the format specified representing the system time in UTC.

    Limitations

    As this function converts the local time, it may not accurately represent the true time in UTC.

    CLOCK_UTC() cannot be used as part of an index definition, this includes the indexed fields and the WHERE clause of the index.

    If this function is called multiple times within the same query then the values returned may differ, particularly if the query takes a long time to run. To avoid inconsistencies between multiple calls to CLOCK_UTC() within a single query, use NOW_UTC() instead.

    Examples

    SELECT CLOCK_UTC() as full_date, CLOCK_UTC('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2018-01-23T21:54:03.593Z",
        "short_date": "2018-01-23"
      }
    ]

    DATE_ADD_MILLIS(date1, n, part)

    Description

    Performs date arithmetic on a particular component of an Epoch/UNIX timestamp value. This calculation is specified by the arguments n and part.

    + For example, a value of 3 for n and a value of day for part would add 3 days to the date specified by date1.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing an Epoch/UNIX timestamp in milliseconds.

    If this argument is not an integer then null is returned.

    n

    The value to increment the date component by. This value must be an integer, or any valid expression which evaluates to an integer, and may be negative to perform date subtraction.

    If a non-integer is passed to the function then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function then null is returned.

    Return Value

    An integer, representing the result of the calculation as an Epoch/UNIX timestamp in milliseconds.

    Examples

    SELECT DATE_ADD_MILLIS(1463284740000, 3, 'day') as add_3_days,
           DATE_ADD_MILLIS(1463284740000, 3, 'year') as add_3_years,
           DATE_ADD_MILLIS(1463284740000, -3, 'day') as sub_3_days,
           DATE_ADD_MILLIS(1463284740000, -3, 'year') as sub_3_years;
    Results
    [
      {
        "add_3_days": 1463543940000,
        "add_3_years": 1557892740000,
        "sub_3_days": 1463025540000,
        "sub_3_years": 1368590340000
      }
    ]

    DATE_ADD_STR(date1, n, part)

    Description

    Performs date arithmetic on a date string. This calculation is specified by the arguments n and part. For example a value of 3 for n and a value of day for part would add 3 days to the date specified by date1.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing the date in a supported date format.

    n

    The value to increment the date component by. This value must be an integer, or any valid expression which evaluates to an integer, and may be negative to perform date subtraction.

    If a non-integer is passed to the function then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function then null is returned.

    Return Value

    An integer representing the result of the calculation as an Epoch/UNIX timestamp in milliseconds.

    Examples

    SELECT DATE_ADD_STR('2016-05-15 03:59:00Z', 3, 'day') as add_3_days,
           DATE_ADD_STR('2016-05-15 03:59:00Z', 3, 'year') as add_3_years,
           DATE_ADD_STR('2016-05-15 03:59:00Z', -3, 'day') as sub_3_days,
           DATE_ADD_STR('2016-05-15 03:59:00Z', -3, 'year') as sub_3_years;
    Results
    [
      {
        "add_3_days": "2016-05-18T03:59:00Z",
        "add_3_years": "2019-05-15T03:59:00Z",
        "sub_3_days": "2016-05-12T03:59:00Z",
        "sub_3_years": "2013-05-15T03:59:00Z"
      }
    ]

    DATE_DIFF_MILLIS(date1, date2, part)

    Description

    Finds the elapsed time between two Epoch/UNIX timestamps. This elapsed time is measured from the date specified by date2 to the date specified by date1. If date1 is greater than date2, then the value returned will be positive, otherwise the value returned will be negative.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    date2

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds.

    This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    Return Value

    An integer representing the elapsed time (based on the specified part) between both dates.

    Examples

    SELECT DATE_DIFF_MILLIS(1463543940000, 1463284740000, 'day') as add_3_days,
           DATE_DIFF_MILLIS(1557892740000, 1463284740000, 'year') as add_3_years,
           DATE_DIFF_MILLIS(1463025540000, 1463284740000, 'day') as sub_3_days,
           DATE_DIFF_MILLIS(1368590340000, 1463284740000, 'year') as sub_3_years;
    Results
    [
      {
        "add_3_days": 3,
        "add_3_years": 3,
        "sub_3_days": -3,
        "sub_3_years": -3
      }
    ]

    DATE_DIFF_STR(date1, date2, part)

    Description

    Finds the elapsed time between two dates specified as formatted strings. This elapsed time is measured from the date specified by date2 to the date specified by date1. If date1 is greater than date2 then the value returned will be positive, otherwise the value returned will be negative.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    date2

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds.

    This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    Return Value

    An integer representing the elapsed time (based on the specified part) between both dates.

    Examples

    Example 1

    Find the day difference and year difference between two strings.

    SELECT DATE_DIFF_STR('2016-05-18T03:59:00Z', '2016-05-15 03:59:00Z', 'day') as add_3_days,
           DATE_DIFF_STR('2019-05-15T03:59:00Z', '2016-05-15 03:59:00Z', 'year') as add_3_years,
           DATE_DIFF_STR('2016-05-12T03:59:00Z', '2016-05-15 03:59:00Z', 'day') as sub_3_days,
           DATE_DIFF_STR('2013-05-15T03:59:00Z', '2016-05-15 03:59:00Z', 'year') as sub_3_years;
    Results
    [
      {
        "add_3_days": 3,
        "add_3_years": 3,
        "sub_3_days": -3,
        "sub_3_years": -3
      }
    ]
    Example 2

    List all hotel documents that were reviewed between two dates.

    SELECT name, reviews[0].date
    FROM `travel-sample`.inventory.hotel
    WHERE reviews[0].date BETWEEN "2013-01-01 00:00:00 +0100" AND "2014-01-01 00:00:00 +0100";

    The same as:

    SELECT name, reviews[0].date
    FROM `travel-sample`.inventory.hotel
    WHERE reviews[0].date BETWEEN "2013-01-01 %" AND "2014-01-01 %";
    Results
    [
      {
        "date": "2013-06-22 18:33:50 +0300",
        "name": "Medway Youth Hostel"
      },
      {
        "date": "2013-06-13 01:39:18 +0300",
        "name": "Le Clos Fleuri"
      },
      {
        "date": "2013-07-12 12:18:02 +0300",
        "name": "Glasgow Grand Central"
      },
      {
        "date": "2013-07-02 14:32:55 +0300",
        "name": "The George Hotel"
      },
      {
        "date": "2013-12-05 09:27:07 +0300",
        "name": "Bacara Resort & Spa"
      },
      {
        "date": "2013-01-10 12:48:39 +0300",
        "name": "Once Brewed YHA Hostel"
      },
      {
        "date": "2013-09-12 02:57:37 +0300",
        "name": "Sandy Patch"
      },
      {
        "date": "2013-12-18 22:36:14 +0300",
        "name": "The Granary at Roch Mill"
      },
      {
        "date": "2013-05-08 17:54:41 +0300",
        "name": "Alberta House B&B"
      },
      // ...
    ]
    When querying between two dates, you must specify the full date (with time and time zone) or use the wildcard character (%).

    DATE_FORMAT_STR(date1, fmt)

    Description

    Converts datetime strings from one supported date string format to a different supported date string format.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format.

    If this argument is not a valid date string then null is returned.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    If an incorrect format is specified then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified.

    Examples

    SELECT DATE_FORMAT_STR('2016-05-15T00:00:23+00:00', '1111-11-11') as full_to_short,
           DATE_FORMAT_STR('2016-05-15', '1111-11-11T00:00:00+00:00') as short_to_full,
           DATE_FORMAT_STR('01:10:05', '1111-11-11T01:01:01Z') as time_to_full;
    Results
    [
      {
        "full_to_short": "2016-05-15",
        "short_to_full": "2016-05-15T00:00:00-07:00",
        "time_to_full": "0000-01-01T01:10:05-08:00"
      }
    ]

    DATE_PART_MILLIS(date1, part [, tz])

    Description

    Extracts the value of a given date component from an Epoch/UNIX timestamp value.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to convert the local time to.

    Optional argument. Defaults to the system timezone if not specified. If an incorrect time zone is provided, then null is returned.

    Return Value

    An integer representing the value of the component extracted from the timestamp.

    Examples

    SELECT DATE_PART_MILLIS(1463284740000, 'day') as day_local,
           DATE_PART_MILLIS(1463284740000, 'day', 'America/Tijuana') as day_pst,
           DATE_PART_MILLIS(1463284740000, 'day', 'UTC') as day_utc,
           DATE_PART_MILLIS(1463284740000, 'month') as month,
           DATE_PART_MILLIS(1463284740000, 'week') as week,
           DATE_PART_MILLIS(1463284740000, 'year') as year;
    Results
    [
      {
        "day_local": 14,
        "day_pst": 14,
        "day_utc": 15,
        "month": 5,
        "week": 20,
        "year": 2016
      }
    ]

    DATE_PART_STR(date1, part)

    Description

    Extracts the value of a given date component from a date string.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    Return Value

    An integer representing the value of the component extracted from the timestamp.

    Examples

    SELECT DATE_PART_STR('2016-05-15T03:59:00Z', 'day') as day,
           DATE_PART_STR('2016-05-15T03:59:00Z', 'millisecond') as millisecond,
           DATE_PART_STR('2016-05-15T03:59:00Z', 'month') as month,
           DATE_PART_STR('2016-05-15T03:59:00Z', 'week') as week,
           DATE_PART_STR('2016-05-15T03:59:00Z', 'year') as year;
    Results
    [
      {
        "day": 15,
        "millisecond": 0,
        "month": 5,
        "week": 20,
        "year": 2016
      }
    ]

    DATE_RANGE_MILLIS(date1, date2, part [,n])

    Description

    Generates an array of dates from the start date specified by date1 and the end date specified by date2, as Epoch/UNIX timestamps. The difference between each subsequent generated date can be adjusted.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    date2

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds.

    This is the value that is subtracted from date1.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    n

    An integer, or any valid expression which evaluates to an integer, representing the value by which to increment the part component for each generated date.

    Optional argument. If not specified, this defaults to 1. If a value which is not an integer is specified, then null is returned.

    Return Value

    An array of integers representing the generated dates, as Epoch/UNIX timestamps, between date1 and date2.

    Limitations

    It is possible to generate very large arrays using this function. In some cases the query engine may be unable to process all of these and cause excessive resource consumption. It is therefore recommended that you first validate the inputs to this function to ensure that the generated result is a reasonable size.

    If the start date is greater than the end date passed to the function then an error will not be thrown, but the result array will be empty. An array of descending dates can be generated by setting the start date greater than the end date and specifying a negative value for n.

    Examples

    Example 1

    Range of milliseconds by month.

    SELECT DATE_RANGE_MILLIS(1480752000000, 1475478000000, 'month', -1) as Milliseconds;
    Results
    [
      {
        "Milliseconds": [
          1480752000000,
          1478156400000
        ]
      }
    ]
    Example 2

    Range of milliseconds by previous month.

    SELECT DATE_RANGE_MILLIS(1480752000000, 1449129600000, 'month', -1) as Months;
    Results
    [
      {
        "Months": [
          1480752000000,
          1478156400000,
          1475478000000,
          1472886000000,
          1470207600000,
          1467529200000,
          1464937200000,
          1462258800000,
          1459666800000,
          1456992000000,
          1454486400000,
          1451808000000
        ]
      }
    ]

    DATE_RANGE_STR(start_date, end_date, date_interval [, quantity_int ])

    Description

    Generates an array of date strings between the start date and end date, calculated by the interval and quantity values. The input dates can be in any of the supported date formats.

    Arguments

    start_date

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date used as the start date of the array generation.

    If this argument is not an integer, then null is returned.

    end_date

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date used as the end date of the array generation, and this value is exclusive, that is, the end date will not be included in the result.

    If this argument is not an integer, then null is returned.

    date_interval

    A string, or any valid expression which evaluates to a string, representing the component of the date to increment.

    If an invalid part is passed to the function, then null is returned.

    quantity_int

    An integer, or any valid expression which evaluates to an integer, representing the value by which to increment the interval component for each generated date.

    Optional argument. If not specified, this defaults to 1. If a value which is not an integer is specified, then null is returned.

    Return Value

    An array of strings representing the generated dates, as date strings, between start_date and end_date.

    Limitations

    • It is possible to generate very large arrays using this function. In some cases the query engine may be unable to process all of these and cause excessive resource consumption. It is therefore recommended that you first validate the inputs of this function to ensure that the generated result is a reasonable size.

    • If the start_date is greater than the end_date, then an error will not be thrown, but the result array will be empty. An array of descending dates can be generated by setting the start_date greater than the end_date and specifying a negative value for quantity_number.

    • From 4.6.2, both specified dates can be different acceptable date formats; but prior to 4.6.2, both specified dates must have the same string format, otherwise null will be returned. To ensure that both dates have the same format, you should use DATE_FORMAT_STR().

    Examples

    Example 1

    Ranges by quarters.

    SELECT DATE_RANGE_STR('2015-11-30T15:04:05.999', '2017-04-14T15:04:06.998', 'quarter')
    AS Quarters;
    Results
    [
      {
        "Quarters": [
          "2015-11-30T15:04:05.999",
          "2016-03-01T15:04:05.999",
          "2016-06-01T15:04:05.999",
          "2016-09-01T15:04:05.999",
          "2016-12-01T15:04:05.999",
          "2017-03-01T15:04:05.999"
        ]
      }
    ]
    Example 2

    Ranges by a single day.

    SELECT DATE_RANGE_STR('2016-01-01T15:04:05.999', '2016-01-05T15:04:05.998', 'day', 1)
    AS Days;
    Results
    [
      {
        "Days": [
          "2016-01-01T15:04:05.999",
          "2016-01-02T15:04:05.999",
          "2016-01-03T15:04:05.999",
          "2016-01-04T15:04:05.999"
        ]
      }
    ]
    Example 3

    Ranges by four months.

    SELECT DATE_RANGE_STR('2018-01-01','2019-01-01', 'month', 4)
    AS Months;
    Results
    [
      {
        "Months": [
          "2018-01-01",
          "2018-05-01",
          "2018-09-01"
        ]
      }
    ]
    Example 4

    Ranges by previous days.

    SELECT DATE_RANGE_STR('2016-01-05T15:04:05.999', '2016-01-01T15:04:06.998', 'day', -1)
    AS Previous;
    Results
    [
      {
        "Previous": [
          "2016-01-05T15:04:05.999",
          "2016-01-04T15:04:05.999",
          "2016-01-03T15:04:05.999",
          "2016-01-02T15:04:05.999"
        ]
      }
    ]
    Example 5

    Ranges by month.

    SELECT DATE_RANGE_STR('2015-01-01T01:01:01', '2015-12-11T00:00:00', 'month', 1)
    AS Months;
    Results
    [
      {
        "Months": [
          "2015-01-01T01:01:01",
          "2015-02-01T01:01:01",
          "2015-03-01T01:01:01",
          "2015-04-01T01:01:01",
          "2015-05-01T01:01:01",
          "2015-06-01T01:01:01",
          "2015-07-01T01:01:01",
          "2015-08-01T01:01:01",
          "2015-09-01T01:01:01",
          "2015-10-01T01:01:01",
          "2015-11-01T01:01:01",
          "2015-12-01T01:01:01"
        ]
      }
    ]

    DATE_TRUNC_MILLIS(date1, part)

    Description

    Truncates an Epoch/UNIX timestamp up to the specified date component.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the date used as the date to truncate.

    If this argument is not an integer, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component to truncate to. This function accepts the components millennium, century, decade, year, quarter, month, week, and iso_week.

    If an invalid part is specified, then null is returned.

    Return Value

    An integer representing the truncated timestamp in Epoch/UNIX time.

    Limitations

    In some cases, where the timestamp is smaller than the duration of the provided part, this function returns the incorrect result. It is recommended that you do not use this function for very small Epoch/UNIX timestamps.

    Examples

    SELECT DATE_TRUNC_MILLIS(1463284740000, 'day') as day,
           DATE_TRUNC_MILLIS(1463284740000, 'month') as month,
           DATE_TRUNC_MILLIS(1463284740000, 'year') as year;
    Results
    [
      {
        "day": 1463270400000,
        "month": 1462147200000,
        "year": 1451696400000
      }
    ]

    DATE_TRUNC_STR(date1, part)

    Description

    Truncates a date string up to the specified date component.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date that is truncated.

    If this argument is not a valid date format, then null is returned.

    part

    A string, or any valid expression which evaluates to a string, representing the component to truncate to. This function accepts the components millennium, century, decade, year, quarter, month, week, and iso_week.

    If an invalid part is specified, then null is returned.

    Return Value

    A date string representing the truncated date.

    Examples

    SELECT DATE_TRUNC_STR('2016-05-18T03:59:00Z', 'day') as day,
           DATE_TRUNC_STR('2016-05-18T03:59:00Z', 'month') as month,
           DATE_TRUNC_STR('2016-05-18T03:59:00Z', 'year') as year;
    Results
    [
      {
        "day": "2016-05-18T00:00:00Z",
        "month": "2016-05-01T00:00:00Z",
        "year": "2016-01-01T00:00:00Z"
      }
    ]

    DURATION_TO_STR(duration)

    Description

    Converts a number into a human-readable time duration with units.

    Arguments

    duration

    A number, or any valid expression which evaluates to a number, which represents the duration to convert to a string. This value is specified in nanoseconds (1×10-9 seconds).

    If a value which is not a number is specified, then null is returned.

    Return Value

    A string representing the human-readable duration.

    Examples

    SELECT DURATION_TO_STR(2000) as microsecs,
           DURATION_TO_STR(2000000) as millisecs,
           DURATION_TO_STR(2000000000) as secs;
    Results
    [
      {
        "microsecs": "2µs",
        "millisecs": "2ms",
        "secs": "2s"
      }
    ]

    MILLIS(date1)

    Description

    Converts a date string to Epoch/UNIX milliseconds.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date to convert to Epoch/UNIX milliseconds.

    If this argument is not a valid date format, then null is returned.

    Return Value

    An integer representing the date string converted to Epoch/UNIX milliseconds.

    Examples

    SELECT MILLIS("2016-05-15T03:59:00Z") as DateStringInMilliseconds;
    Results
    [
      {
        "DateStringInMilliseconds": 1463284740000
      }
    ]

    MILLIS_TO_LOCAL(date1 [, fmt])

    Alias for MILLIS_TO_STR().

    MILLIS_TO_STR(date1 [, fmt ])

    Description

    Converts an Epoch/UNIX timestamp into the specified date string format.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the date to convert.

    If this argument is not an integer, then null is returned.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If unspecified or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string representing the local date in the specified format.

    Limitations

    In some cases, where the timestamp is smaller than the duration of the provided part, this function returns the incorrect result. It is recommended that you do not use this function for very small Epoch/UNIX timestamps.

    Examples

    SELECT MILLIS_TO_STR(1463284740000) as full_date,
           MILLIS_TO_STR(1463284740000, 'invalid format') as invalid_format,
           MILLIS_TO_STR(1463284740000, '1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2016-05-14T20:59:00-07:00",
        "invalid_format": "2016-05-14T20:59:00-07:00",
        "short_date": "2016-05-14"
      }
    ]

    MILLIS_TO_TZ(date1, tz [, fmt])

    Description

    Converts an Epoch/UNIX timestamp into the specified time zone in the specified date string format.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the date to convert.

    If this argument is not an integer, then null is returned.

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to convert the local time to. Optional argument. Defaults to the system timezone if not specified.

    If an incorrect time zone is provided, then null is returned.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string representing the date in the specified timezone in the specified format..

    Examples

    SELECT MILLIS_TO_TZ(1463284740000, 'America/New_York') as est,
    	   MILLIS_TO_TZ(1463284740000, 'Asia/Kolkata') as ist,
    	   MILLIS_TO_TZ(1463284740000, 'UTC') as utc;
    Results
    [
      {
        "est": "2016-05-14T23:59:00-04:00",
        "ist": "2016-05-15T09:29:00+05:30",
        "utc": "2016-05-15T03:59:00Z"
      }
    ]

    MILLIS_TO_UTC(date1 [, fmt])

    Description

    Converts an Epoch/UNIX timestamp into local time in the specified date string format.

    Arguments

    date1

    An integer, or any valid expression which evaluates to an integer, representing a Epoch/UNIX timestamp in milliseconds. This is the date to convert to UTC.

    If this argument is not an integer, then null is returned.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If unspecified or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string representing the date in UTC in the specified format.

    Examples

    SELECT MILLIS_TO_UTC(1463284740000) as full_date,
           MILLIS_TO_UTC(1463284740000, 'invalid format') as invalid_format,
           MILLIS_TO_UTC(1463284740000, '1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2016-05-15T03:59:00Z",
        "invalid_format": "2016-05-15T03:59:00Z",
        "short_date": "2016-05-15"
      }
    ]

    MILLIS_TO_ZONE_NAME(date1, tz [, fmt])

    Alias for MILLIS_TO_TZ()

    NOW_LOCAL([fmt])

    Description

    The timestamp of the query as date string in the system timezone. Will not vary during a query.

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If no format or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date time string in the format specified.

    Limitations

    If this function is called multiple times within the same query it will always return the same time. If you wish to use the system time when the function is evaluated, use CLOCK_LOCAL() instead.

    Examples

    Example 1

    Various arguments of NOW_LOCAL().

    SELECT NOW_LOCAL() as full_date,
           NOW_LOCAL('invalid date') as invalid_date,
           NOW_LOCAL('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2018-01-23T14:03:40.26-08:00",
        "invalid_date": "2018-01-23T14:03:40.26-08:00",
        "short_date": "2018-01-23"
      }
    ]
    Example 2

    Difference between NOW_LOCAL() and CLOCK_LOCAL().

    SELECT NOW_LOCAL(), NOW_LOCAL(), NOW_LOCAL(), NOW_LOCAL(), NOW_LOCAL(), CLOCK_LOCAL();
    Results
    [
      {
        "$1": "2018-01-23T14:06:20.254-08:00",
        "$2": "2018-01-23T14:06:20.254-08:00",
        "$3": "2018-01-23T14:06:20.254-08:00",
        "$4": "2018-01-23T14:06:20.254-08:00",
        "$5": "2018-01-23T14:06:20.254-08:00",
        "$6": "2018-01-23T14:06:20.256-08:00"
      }
    ]

    NOW_MILLIS()

    Description

    The timestamp of the query as an Epoch/UNIX timestamp. Will not vary during a query.

    Arguments

    This function accepts no arguments.

    Return Value

    A floating point number representing the Epoch/UNIX timestamp of the query.

    Limitations

    If this function is called multiple times within the same query it will always return the same time. If you wish to use the system time when the function is evaluated, use CLOCK_MILLIS() instead.

    Examples

    Example 1

    The time now in milliseconds.

    SELECT NOW_MILLIS() as NowInMilliseconds;
    Results
    [
      {
        "NowInMilliseconds": 1516745378065.12
      }
    ]
    Example 2

    Difference between NOW_MILLIS() and CLOCK_MILLIS().

    SELECT NOW_MILLIS(), NOW_MILLIS(), NOW_MILLIS(), NOW_MILLIS(), CLOCK_MILLIS();
    Results
    [
      {
        "$1": 1516745528579.607,
        "$2": 1516745528579.607,
        "$3": 1516745528579.607,
        "$4": 1516745528580.29
      }
    ]

    NOW_TZ(tz [, fmt])

    Description

    The timestamp of the query as date string in the specified timezone. Will not vary during a query.

    Arguments

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to convert the query timestamp to.

    If an incorrect time zone is provided then null is returned.

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If unspecified or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified representing the timestamp of the query in the specified timezone.

    Limitations

    If this function is called multiple times within the same query it will always return the same time. If you wish to use the system time when the function is evaluated, use CLOCK_TZ() instead.

    Examples

    Example 1

    Various arguments for NOW_TZ().

    SELECT NOW_TZ('invalid tz') as invalid_tz,
           NOW_TZ('Asia/Kolkata') as ist,
           NOW_TZ('UTC') as utc,
           NOW_TZ('UTC', '1111-11-11') as utc_short_date;
    Results
    [
      {
        "invalid_tz": null,
        "ist": "2018-01-24T03:43:36.457+05:30",
        "utc": "2018-01-23T22:13:36.457Z",
        "utc_short_date": "2018-01-23"
      }
    ]
    Example 2

    Difference between NOW_TZ() and CLOCK_TZ().

    SELECT NOW_TZ('UTC'), NOW_TZ('UTC'), NOW_TZ('UTC'), CLOCK_TZ('UTC');
    Results
    [
      {
        "$1": "2018-01-23T22:15:59.551Z",
        "$2": "2018-01-23T22:15:59.551Z",
        "$3": "2018-01-23T22:15:59.551Z",
        "$4": "2018-01-23T22:15:59.552Z"
      }
    ]

    NOW_STR([fmt])

    Description

    The timestamp of the query as date string in the system timezone. Will not vary during a query.

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If unspecified or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified representing the timestamp of the query.

    Limitations

    If this function is called multiple times within the same query it will always return the same time. If you wish to use the system time when the function is evaluated, use CLOCK_STR() instead.

    Examples

    Example 1

    Various arguments for NOW_STR().

    SELECT NOW_STR() as full_date,
           NOW_STR('invalid date') as invalid_date,
           NOW_STR('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "2018-01-23T14:16:58.075-08:00",
        "invalid_date": "2018-01-23T14:16:58.075-08:00",
        "short_date": "2018-01-23"
      }
    ]
    Example 2

    Difference between NOW_STR() and CLOCK_STR().

    SELECT NOW_STR(), NOW_STR(), NOW_STR(), NOW_STR(), NOW_STR(), NOW_STR(), CLOCK_STR();
    Results
    [
      {
        "$1": "2018-01-23T14:18:37.605-08:00",
        "$2": "2018-01-23T14:18:37.605-08:00",
        "$3": "2018-01-23T14:18:37.605-08:00",
        "$4": "2018-01-23T14:18:37.605-08:00",
        "$5": "2018-01-23T14:18:37.605-08:00",
        "$6": "2018-01-23T14:18:37.605-08:00",
        "$7": "2018-01-23T14:18:37.607-08:00"
      }
    ]

    NOW_UTC([fmt])

    Description

    The timestamp of the query as date string in UTC. Will not vary during a query.

    Arguments

    fmt

    A string, or any valid expression which evaluates to a string, representing a supported date format to output the result as.

    Optional argument. If unspecified or an incorrect format is specified, then this defaults to the combined full date and time.

    Return Value

    A date string in the format specified representing the timestamp of the query in UTC.

    Limitations

    If this function is called multiple times within the same query it will always return the same time. If you wish to use the system time when the function is evaluated, use CLOCK_MILLIS() instead.

    Examples

    Example 1

    The current UTC time.

    SELECT NOW_UTC() as CurrentUTC;
    Results
    [
      {
        "CurrentUTC": "2018-01-23T22:20:43.971Z"
      }
    ]
    Example 2

    Difference between NOW_UTC() and CLOCK_UTC().

    SELECT NOW_UTC(), NOW_UTC(), NOW_UTC(), NOW_UTC(), NOW_UTC(), NOW_UTC(), NOW_UTC(), CLOCK_UTC();
    Results
    [
      {
        "$1": "2018-01-23T22:21:46.769Z",
        "$2": "2018-01-23T22:21:46.769Z",
        "$3": "2018-01-23T22:21:46.769Z",
        "$4": "2018-01-23T22:21:46.769Z",
        "$5": "2018-01-23T22:21:46.769Z",
        "$6": "2018-01-23T22:21:46.769Z",
        "$7": "2018-01-23T22:21:46.769Z",
        "$8": "2018-01-23T22:21:46.77Z"
      }
    ]

    STR_TO_DURATION(duration)

    Description

    Converts a string representation of a time duration into nanoseconds. This accepts the following units:

    • nanoseconds (ns)

    • microseconds (us or µs)

    • milliseconds (ms)

    • seconds (s)

    • minutes (m)

    • hours (h)

    Arguments

    duration

    A string, or any valid expression which evaluates to a string, representing the duration to convert.

    If an invalid duration string is specified, then null is returned.

    Return Value

    A single integer representing the duration in nanoseconds.

    Examples

    SELECT STR_TO_DURATION('1h') as hour,
    STR_TO_DURATION('1us') as microsecond,
    STR_TO_DURATION('1ms') as millisecond,
    STR_TO_DURATION('1m') as minute,
    STR_TO_DURATION('1ns') as nanosecond,
    STR_TO_DURATION('1s') as second;
    Results
    [
      {
        "hour": 3600000000000,
        "microsecond": 1000,
        "millisecond": 1000000,
        "minute": 60000000000,
        "nanosecond": 1,
        "second": 1000000000
      }
    ]

    STR_TO_MILLIS(date1 [, format])

    Description

    Converts a date string to Epoch/UNIX milliseconds.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing the date to convert to Epoch/UNIX milliseconds.

    If this argument is not a valid date format, then null is returned.

    format

    A string, or any valid expression which evaluates to a string, representing the expected format of the input date string, using the Go language reference date.

    Optional argument. If not specified, the input date string must be in a supported date format. If an incorrect format is provided, then null is returned.

    Return Value

    An integer representing the date string converted to Epoch/UNIX milliseconds.

    Examples

    Example 1
    SELECT STR_TO_MILLIS("2016-05-15T03:59:00Z") AS Milliseconds;
    Results
    [
      {
        "Milliseconds": 1463284740000
      }
    ]
    Example 2
    SELECT STR_TO_MILLIS("19/08/2011 6:33:23+0000", "02/01/2006 15:04:05Z0700")
    AS Milliseconds;
    Results
    [
      {
        "Milliseconds": 1313735603000
      }
    ]

    STR_TO_UTC(date1)

    Description

    Converts a date string into the equivalent date in UTC. The output date format follows the date format of the date passed as input.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date to convert to UTC.

    If this argument is not a valid date format, then null is returned.

    Return Value

    A single date string representing the date string converted to UTC.

    Examples

    SELECT STR_TO_UTC('1111-11-11T00:00:00+08:00') as full_date,
    STR_TO_UTC('1111-11-11') as short_date;
    Results
    [
      {
        "full_date": "1111-11-10T16:00:00Z",
        "short_date": "1111-11-11"
      }
    ]

    STR_TO_TZ(date1, tz)

    Description

    Converts a date string to its equivalent in the specified timezone. The output date format follows the date format of the date passed as input.

    Arguments

    date1

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date to convert to UTC.

    If this argument is not a valid date format then null is returned.

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to convert the local time to.

    If this argument is not a valid timezone, then null is returned.

    Return Value

    A single date string representing the date string converted to the specified timezone.

    Examples

    SELECT STR_TO_TZ('1111-11-11T00:00:00+08:00', 'America/New_York') as est,
        STR_TO_TZ('1111-11-11T00:00:00+08:00', 'UTC') as utc,
        STR_TO_TZ('1111-11-11', 'UTC') as utc_short;
    Results
    [
      {
        "est": "1111-11-10T11:00:00-05:00",
        "utc": "1111-11-10T16:00:00Z",
        "utc_short": "1111-11-11"
      }
    ]

    STR_TO_ZONE_NAME(date1, tz)

    Alias for STR_TO_TZ().

    WEEKDAY_MILLIS(expr [, tz ])

    Description

    Converts a date string to its equivalent in the specified timezone. The output date format follows the date format of the date passed as input.

    Arguments

    expr

    An integer, or any valid expression which evaluates to an integer, representing an Epoch/UNIX timestamp in milliseconds.

    tz

    A string, or any valid expression which evaluates to a string, representing the timezone to for the expr argument.

    Optional argument. Defaults to the system timezone if not specified. If an incorrect time zone is provided then null is returned.

    Return Value

    A single date string representing the date string converted to the specified timezone.

    Examples

    SELECT WEEKDAY_MILLIS(1486237655742, 'America/Tijuana') as Day;
    Results
    [
      {
        "Day": "Saturday"
      }
    ]

    WEEKDAY_STR(date)

    Description

    Returns the day of the week string value from the input date string. Returns the weekday name from the input date in Unix timestamp. Note that his function returns the string value of the day of the week, where DATE_PART_STR() with part = "dow" returns an integer value of the weekday (0-6).

    Arguments

    date

    A string, or any valid expression which evaluates to a string, representing a date in a supported date format. This is the date to convert to UTC.

    If this argument is not a valid date format then null is returned.

    Return Value

    The text string name of the day of the week, such as "Monday" or "Friday".

    Examples

    SELECT WEEKDAY_STR('2017-02-05') as Day;
    Results
    [
      {
        "Day": "Sunday"
      }
    ]