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Return Type

Name(Signature)

Description

OSS

bigint

count(*), count(expr), count(DISTINCT expr[, expr...])

count(*) - Returns the total number of retrieved rows, including rows containing NULL values.

count(expr) - Returns the number of rows for which the supplied expression is non-NULL.

count(DISTINCT expr[, expr]) - Returns the number of rows for which the supplied expression(s) are unique and non-NULL. Execution of this can be optimized with hive.optimize.distinct.rewrite.

Source codeGenericUDAFCount

double

sum(col), sum(DISTINCT col)

Returns the sum of the elements in the group or the sum of the distinct values of the column in the group.

Source codeGenericUDAFSum

double

avg(col), avg(DISTINCT col)

Returns the average of the elements in the group or the average of the distinct values of the column in the group.

Source codeGenericUDAFAverage

double

min(col)

Returns the minimum of the column in the group.

Source codeGenericUDAFMin

double

max(col)

Returns the maximum value of the column in the group.

Source codeGenericUDAFMax

double

variance(col), var_pop(col)

Returns the variance of a numeric column in the group.

Source codeGenericUDAFVariance

double

var_samp(col)

Returns the unbiased sample variance of a numeric column in the group.

Source codeGenericUDAFVarianceSample

double

stddev_pop(col)

Returns the standard deviation of a numeric column in the group.

Source codeGenericUDAFStd

double

stddev_samp(col)

Returns the unbiased sample standard deviation of a numeric column in the group.

Source codeGenericUDAFStdSample

double

covar_pop(col1, col2)

Returns the population covariance of a pair of numeric columns in the group.

Source codeGenericUDAFCovariance

double

covar_samp(col1, col2)

Returns the sample covariance of a pair of numeric columns in the group.

Source codeGenericUDAFCovarianceSample

double

corr(col1, col2)

Returns the Pearson coefficient of correlation of a pair of numeric columns in the group.

Source codeGenericUDAFCorrelation

double

percentile(BIGINT col, p)

Returns the exact pth percentile of a column in the group (does not work with floating point types). p must be between 0 and 1. NOTE: A true percentile can only be computed for integer values. Use PERCENTILE_APPROX if your input is non-integral.

Source codeUDAFPercentile

array<double>

percentile(BIGINT col, array(p1 [, p2]...))

Returns the exact percentiles p1, p2, ... of a column in the group (does not work with floating point types). pi must be between 0 and 1. NOTE: A true percentile can only be computed for integer values. Use PERCENTILE_APPROX if your input is non-integral.


double

percentile_approx(DOUBLE col, p [, B])

Returns an approximate pth percentile of a numeric column (including floating point types) in the group. The B parameter controls approximation accuracy at the cost of memory. Higher values yield better approximations, and the default is 10,000. When the number of distinct values in col is smaller than B, this gives an exact percentile value.

Source codeGenericUDAFPercentileApprox

array<double>

percentile_approx(DOUBLE col, array(p1 [, p2]...) [, B])

Same as above, but accepts and returns an array of percentile values instead of a single one.


double

regr_avgx(independent, dependent)

Equivalent to avg(dependent). 


double

regr_avgy(independent, dependent)

Equivalent to avg(independent). 


double

regr_count(independent, dependent)

Returns the number of non-null pairs used to fit the linear regression line. 


double

regr_intercept(independent, dependent)

Returns the y-intercept of the linear regression line, i.e. the value of b in the equation dependent = a * independent + b.


double

regr_r2(independent, dependent)

Returns the coefficient of determination for the regression. 


double

regr_slope(independent, dependent)

Returns the slope of the linear regression line, i.e. the value of an in the equation dependent = a * independent + b. 


double

regr_sxx(independent, dependent)

Equivalent to regr_count(independent, dependent) * var_pop(dependent). 


double

regr_sxy(independent, dependent)

Equivalent to regr_count(independent, dependent) * covar_pop(independent, dependent). 


doubleregr_syy(independent, dependent)

Equivalent to regr_count(independent, dependent) * var_pop(independent).


array<struct {'x','y'}>

histogram_numeric(col, b)

Computes a histogram of a numeric column in the group using b non-uniformly spaced bins. The output is an array of size b of double-valued (x,y) coordinates that represent the bin centers and heights

Source codeGenericUDAFHistogramNumeric

array

collect_set(col)

Returns a set of objects with duplicate elements eliminated.

Source codeGenericUDAFCollectSet

array

collect_list(col)

Returns a list of objects with duplicates. 

Source codeGenericUDAFCollectList

intntile(INTEGER x)

Divides an ordered partition into x groups called buckets and assign a bucket number to each row in the partition. This allows easy calculation of tertiles, quartiles, deciles, percentiles, and other common summary statistics.

Source codeGenericUDAFNTile


Tip

Most of the UDAF ignore NULL values. 

...

Row-set columns types

Name(Signature)

Description

OSS

T

explode(ARRAY<T> a)

Explodes an array to multiple rows. Returns a row-set with a single column (col), one row for each element from the array.

 Source code GenericUDTFExplode


Tkey,Tvalue

explode(MAP<Tkey,Tvalue> m)

Explodes a map to multiple rows. Returns a row-set with a two columns (key,value) , one row for each key-value pair from the input map.

int,Tposexplode(ARRAY<T> a)Explodes an array to multiple rows with an additional positional column of int type (position of items in the original array, starting with 0). Returns a row-set with two columns (pos,val), one row for each element from the array.Source codeGenericUDTFPosExplode

T1,...,Tn

inline(ARRAY<STRUCT<f1:T1,...,fn:Tn>> a)

Explodes an array of structs to multiple rows. Returns a row-set with N columns (N = number of top level elements in the struct), one row per struct from the array.

Source codeGenericUDTFInline

T1,...,Tn/rstack(int r,T1 V1,...,Tn/r Vn)Breaks up n values V1,...,Vn into r rows. Each row will have n/r columns. r must be constant.Source codeGenericUDTFStack
string1,...,stringnjson_tuple(string jsonStr,string k1,...,string kn)Takes JSON string and a set of n keys, and returns a tuple of n values. This is a more efficient version of the get_json_object UDF because it can get multiple keys with just one call.Source codeGenericUDTFJSONTuple

string 1,...,stringn

parse_url_tuple(string urlStr,string p1,...,string pn)

Takes URL string and a set of n URL parts, and returns a tuple of n values. This is similar to the parse_url() UDF but can extract multiple parts at once out of a URL. Valid part names are: HOST, PATH, QUERY, REF, PROTOCOL, AUTHORITY, FILE, USERINFO, QUERY:<KEY>.

Source codeGenericUDTFParseUrlTuple

String Functions

There is no good engine without string manipulation functions. Apache Hive has rich built-in string functions. 

Return Type

Name(Signature)

Description

OSS

int

ascii(string str)

Returns the numeric value of the first character of str.

 Source codeUDFAscii

string

base64(binary bin)

Converts the argument from binary to a base64 string.

Source codeUDFBase64

intcharacter_length(string str)Returns the number of UTF-8 characters contained in str. The function char_length is shorthand for this function.Source codeGenericUDFCharacterLength
stringchr(bigint|double A)Returns the ASCII character having the binary equivalent to A. If A is larger than 256 the result is equivalent to chr(A % 256). Example: select chr(88); returns "X".Source codeUDFChr

string

concat(string|binary A, string|binary B...)

Returns the string or bytes resulting from concatenating the strings or bytes passed in as parameters in order. For example, concat('foo', 'bar') results in 'foobar'. Note that this function can take any number of input strings.

Source codeGenericUDFConcat

array<struct<string,double>>

context_ngrams(array<array<string>>, array<string>, int K, int pf)

Returns the top-k contextual N-grams from a set of tokenized sentences, given a string of "context". See StatisticsAndDataMining for more information.

Source codeGenericUDAFContextNGrams

string

concat_ws(string SEP, string A, string B...)

Like concat() above, but with custom separator SEP.


Source codeGenericUDFConcatWS

string

concat_ws(string SEP, array<string>)

Like concat_ws() above, but taking an array of strings.

string

decode(binary bin, string charset)

Decodes the first argument into a String using the provided character set (one of 'US-ASCII', 'ISO-8859-1', 'UTF-8', 'UTF-16BE', 'UTF-16LE', 'UTF-16'). If either argument is null, the result will also be null.

Source codeGenericUDFDecode

stringelt(N int,str1 string,str2 string,str3 string,...)

Return string at index number. For example elt(2,'hello','world') returns 'world'. Returns NULL if N is less than 1 or greater than the number of arguments.

Source codeGenericUDFElt

binary

encode(string src, string charset)

Encodes the first argument into a BINARY using the provided character set (one of 'US-ASCII', 'ISO-8859-1', 'UTF-8', 'UTF-16BE', 'UTF-16LE', 'UTF-16'). If either argument is null, the result will also be null. 

Source codeGenericUDFEncode

intfield(val T,val1 T,val2 T,val3 T,...)

Returns the index of val in the val1,val2,val3,... list or 0 if not found. For example field('world','say','hello','world') returns 3.
All primitive types are supported, arguments are compared using str.equals(x). If val is NULL, the return value is 0.

Source codeGenericUDFField

int

find_in_set(string str, string strList)

Returns the first occurance of str in strList where strList is a comma-delimited string. Returns null if either argument is null. Returns 0 if the first argument contains any commas. For example, find_in_set('ab', 'abc,b,ab,c,def') returns 3.

Source codeUDFFindInSet

string

format_number(number x, int d)

Formats the number X to a format like '#,###,###.##', rounded to D decimal places, and returns the result as a string. If D is 0, the result has no decimal point or fractional part.

Source codeGenericUDFFormatNumber

string

get_json_object(string json_string, string path)

Extracts json object from a json string based on json path specified, and returns json string of the extracted json object. It will return null if the input json string is invalid.

Note
titleNote

The json path can only have the characters [0-9a-z_], i.e., no upper-case or special characters. Also, the keys *cannot start with numbers.* This is due to restrictions on Hive column names.


Source codeUDFJson

boolean

in_file(string str, string filename)

Returns true if the string str appears as an entire line in filename.

Source codeGenericUDFInFile

int

instr(string str, string substr)

Returns the position of the first occurrence of substr in str. Returns null if either of the arguments are null and returns 0 if substr could not be found in str. Be aware that this is not zero-based. The first character in str has index 1.

Source codeGenericUDFInstr

int

length(string A)

Returns the length of the string.

Source codeGenericUDFLength

int

locate(string substr, string str[, int pos])

Returns the position of the first occurrence of substr in str after position pos.

Source codeGenericUDFLocate

string

lower(string A) lcase(string A)

Returns the string resulting from converting all characters of B to lower case. For example, lower('fOoBaR') results in 'foobar'.

Source codeGenericUDFLower

string

lpad(string str, int len, string pad)

Returns str, left-padded with pad to a length of len. If str is longer than len, the return value is shortened to len characters. In case of empty pad string, the return value is null.

Source codeGenericUDFLpad

string

ltrim(string A)

Returns the string resulting from trimming spaces from the beginning(left hand side) of A. For example, ltrim(' foobar ') results in 'foobar '.

Source codeGenericUDFLTrim

array<struct<string,double>>

ngrams(array<array<string>>, int N, int K, int pf)

Returns the top-k N-grams from a set of tokenized sentences, such as those returned by the sentences() UDAF. See StatisticsAndDataMining for more information.

Source codeGenericUDAFnGrams

intoctet_length(string str)Returns the number of octets required to hold the string str in UTF-8 encoding.  Note that octet_length(str) can be larger than character_length(str).Source codeGenericUDFOctetLength

string

parse_url(string urlString, string partToExtract [, string keyToExtract])

Returns the specified part from the URL. Valid values for partToExtract include HOST, PATH, QUERY, REF, PROTOCOL, AUTHORITY, FILE, and USERINFO. For example, parse_url('http://facebook.com/path1/p.php?k1=v1&k2=v2#Ref1', 'HOST') returns 'facebook.com'. Also, a value of a particular key in QUERY can be extracted by providing the key as the third argument, for example, parse_url('http://facebook.com/path1/p.php?k1=v1&k2=v2#Ref1', 'QUERY', 'k1') returns 'v1'.

Source codeUDFParseUrl

string

printf(String format, Obj... args)

Returns the input formatted according to printf-style format strings.

Source codeGenericUDFPrintf

stringquote(String text)

Returns the quoted string 

InputOutput
NULLNULL
DONT'DONT'
DON'T'DON\'T'

Status
colourGreen
titleNew
Includes escape character for any single quotes in Apache Hive 4.0.0

Source codeGenericUDFQuote

string

regexp_extract(string subject, string pattern, int index)

Returns the string extracted using the pattern. For example, regexp_extract('foothebar', 'foo(.*?)(bar)', 2) returns 'bar.' Note that some care is necessary in using predefined character classes: using '\s' as the second argument will match the letter s; '\\s' is necessary to match whitespace, etc. The 'index' parameter is the Java regex Matcher group() method index. 

Source codeUDFRegExpExtract

string

regexp_replace(string INITIAL_STRING, string PATTERN, string REPLACEMENT)

Returns the string resulting from replacing all substrings in INITIAL_STRING that match the java regular expression syntax defined in PATTERN with instances of REPLACEMENT. For example, regexp_replace("foobar", "oo|ar", "") returns 'fb.' Note that some care is necessary in using predefined character classes: using '\s' as the second argument will match the letter s; '\\s' is necessary to match whitespace, etc.

Source codeUDFRegExpReplace

string

repeat(string str, int n)

Repeats str in n times.

Source codeUDFRepeat

stringreplace(string A, string OLD, string NEW)Returns the string A with all non-overlapping occurrences of OLD replaced with NEW. Example: select replace("ababab", "abab", "Z"); returns "Zab".Source codeUDFReplace

string

reverse(string A)

Returns the reversed string.

Source codeUDFReverse

string

rpad(string str, int len, string pad)

Returns str, right-padded with pad to a length of len. If str is longer than len, the return value is shortened to len characters. In case of empty pad string, the return value is null.

Source codeGenericUDFRpad

string

rtrim(string A)

Returns the string resulting from trimming spaces from the end(right hand side) of A. For example, rtrim(' foobar ') results in ' foobar'.

Source codeGenericUDFRTrim

array<array<string>>

sentences(string str, string lang, string locale)

Tokenizes a string of natural language text into words and sentences, where each sentence is broken at the appropriate sentence boundary and returned as an array of words. The 'lang' and 'locale' are optional arguments. For example, sentences('Hello there! How are you?') returns ( ("Hello", "there"), ("How", "are", "you") ).

Source codeGenericUDFSentences

string

space(int n)

Returns a string of n spaces.

Source codeUDFSpace

array

split(string str, string pat)

Splits str around pat (pat is a regular expression).

Source codeGenericUDFSplit

map<string,string>

str_to_map(text[, delimiter1, delimiter2])

Splits text into key-value pairs using two delimiters. Delimiter1 separates text into K-V pairs, and Delimiter2 splits each K-V pair. Default delimiters are ',' for delimiter1 and ':' for delimiter2.

Source codeGenericUDFStringToMap

string

substr(string|binary A, int start) substring(string|binary A, int start)

Returns the substring or slice of the byte array of A starting from start position till the end of string A. For example, substr('foobar', 4) results in 'bar'.

Source codeGenericUDFSubstringIndex



string

substr(string|binary A, int start, int len) substring(string|binary A, int start, int len)

Returns the substring or slice of the byte array of A starting from start position with length len. For example, substr('foobar', 4, 1) results in 'b'.

stringsubstring_index(string A, string delim, int count)Returns the substring from string A before count occurrences of the delimiter delim. If count is positive, everything to the left of the final delimiter (counting from the left) is returned. If count is negative, everything to the right of the final delimiter (counting from the right) is returned. Substring_index performs a case-sensitive match when searching for delim. Example: substring_index('www.apache.org', '.', 2) = 'www.apache'.Source codeGenericUDFSubstringIndex

string

translate(string|char|varchar input, string|char|varchar from, string|char|varchar to)

Translates the input string by replacing the characters present in the from string with the corresponding characters in the to string. This is similar to the translate function in PostgreSQL. If any of the parameters to this UDF are NULL, the result is NULL as well. 

Source codeGenericUDFTranslate

string

trim(string A)

Returns the string resulting from trimming spaces from both ends of A. For example, trim(' foobar ') results in 'foobar'

Source codeGenericUDFTrim

binary

unbase64(string str)

Converts the argument from a base 64 string to BINARY.

Source codeUDFUnbase64

string

upper(string A) ucase(string A)

Returns the string resulting from converting all characters of A to upper case. For example, upper('fOoBaR') results in 'FOOBAR'.

Source codeGenericUDFUpper

stringinitcap(string A)Returns string, with the first letter of each word in uppercase, all other letters in lowercase. Words are delimited by whitespace.Source codeGenericUDFInitCap
intlevenshtein(string A, string B)Returns the Levenshtein distance between two strings. Example: levenshtein('kitten', 'sitting') results in 3.Source codeGenericUDFLevenshtein
stringsoundex(string A)Returns the soundex code of the string. Example: soundex('Miller') results in M460.Source codeGenericUDFSoundex

Date Functions

In many analytical workloads Date is one of the most used built-in functions in Hive. The following list contains the supported built-in date functions in Hive.

Return Type

Name(Signature)

Description

OSS

string

from_unixtime(bigint unixtime[, string pattern])

Converts a number of seconds since epoch (1970-01-01 00:00:00 UTC) to a string representing the timestamp of that moment in the current time zone(using config "hive.local.time.zone") using the specified pattern. If the pattern is missing the default is used ('uuuu-MM-dd HH:mm:ss' or yyyy-MM-dd HH:mm:ss'). Example: from_unixtime(0)=1970-01-01 00:00:00 (hive.local.time.zone=Etc/GMT)

Status
colourGreen
titleNew

As of Hive 4.0.0 the "hive.datetime.formatter" property can be used to control the underlying formatter implementation and as a consequence the accepted patterns and their behavior.  Earlier versions used https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html as the underlying formatter.

Source codeGenericUDFFromUnixTime

bigint

unix_timestamp()

Gets the current Unix timestamp in seconds. This function is not deterministic and its value is not fixed for the scope of a query execution, therefore prevents proper optimization of queries - this has been deprecated since 2.0 in favour of CURRENT_TIMESTAMP constant.



Source codeGenericUDFUnixTimeStamp

bigint

unix_timestamp(string date)

Converts a DateTime string to unix time (seconds since epoch) using the default pattern(s). The default accepted patterns depend on the underlying formatter implementation. The datetime string does not contain a timezone so the conversion uses the local time zone as specified by "hive.local.time.zone" property. Returns null when the conversion fails. Example: unix_timestamp('2009-03-20 11:30:01') = 1237573801

Status
colourGreen
titleNew

As of Hive 4.0.0 the "hive.datetime.formatter" property can be used to control the underlying formatter implementation and as a consequence the accepted patterns and their behavior. Earlier versions used https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html as the underlying formatter.

bigint

unix_timestamp(string date, string pattern)

Converts a datetime string to unix time (seconds since epoch) using the specified pattern. The accepted patterns and their behavior depend on the underlying formatter implementation. Returns null when the conversion fails. Example: unix_timestamp('2009-03-20', 'uuuu-MM-dd') = 1237532400

Status
colourGreen
titleNew

As of Hive 4.0.0 the "hive.datetime.formatter" property can be used to control the underlying formatter implementation, and as a consequence the accepted patterns and their behavior.  Earlier versions used https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html as the underlying formatter.

date

to_date(string timestamp)

Returns the date part of a timestamp date object. Example: to_date("1970-01-01 00:00:00") 


int

year(string date)

Returns the year part of a date or a timestamp string: year("1970-01-01 00:00:00") = 1970, year("1970-01-01") = 1970.

Source codeUDFYear

int

quarter(date/timestamp/string)Returns the quarter of the year for a date, timestamp, or string in the range 1 to 4. Example: quarter('2015-04-08') = 2.

int

month(string date)

Returns the month part of a date or a timestamp string. Example: month("1970-11-01 00:00:00") = 11, month("1970-11-01") = 11.

Source codeUDFMonth

int

day(string date) dayofmonth(date)

Returns the day part of a date or a timestamp string. Example: day("1970-11-01 00:00:00") = 1, day("1970-11-01") = 1.

Source codeUDFDayOfMonth

int

hour(string date)

Returns the hour of the timestamp: Example: hour('2009-07-30 12:58:59') = 12, hour('12:58:59') = 12.

Source codeUDFHour

int

minute(string date)

Returns the minute of the timestamp.

Source codeUDFMinute

int

second(string date)

Returns the second of the timestamp.

Source codeUDFSecond

int

weekofyear(string date)

Returns the week number of a timestamp string. Example: weekofyear("1970-11-01 00:00:00") = 44 or weekofyear("1970-11-01") = 44.

Source codeUDFWeekOfYear

int

extract(field FROM source)

Retrieve fields such as days or hours from the source. The source must be a date, timestamp, interval, or string that can be converted into either a date or timestamp. Supported fields include day, dayofweek, hour, minute, month, quarter, second, week and year.

Examples:

  1. select extract(month from "2016-10-20") results in 10.

  2. select extract(hour from "2016-10-20 05:06:07") results in 5.

  3. select extract(dayofweek from "2016-10-20 05:06:07") results in 5.

  4. select extract(month from interval '1-3' year to month) results in 3.

  5. select extract(minute from interval '3 12:20:30' day to second) results in 20.


int

datediff(string enddate, string startdate)

Returns the number of days from startdate to end date. Example: datediff('2009-03-01', '2009-02-27') = 2.

Source codeGenericUDFDateDiff

date

date_add(date/timestamp/string startdate, tinyint/smallint/int days)

Adds a number of days to startdate. Example: date_add('2008-12-31', 1) = '2009-01-01'.

Source codeGenericUDFDateAdd

date

date_sub(date/timestamp/string startdate, tinyint/smallint/int days)

Subtracts a number of days to startdate: date_sub('2008-12-31', 1) = '2008-12-30'.

Source codeGenericUDFDateSub

timestamp

from_utc_timestamp({any primitive type} ts, string timezone)

Converts a timestamp* in UTC to a given timezone.

* timestamp is a primitive type, including timestamp/date, tinyint/smallint/int/bigint, float/double and decimal.

Fractional values are considered as seconds. Integer values are considered as milliseconds. For example, from_utc_timestamp(2592000.0,'PST'), from_utc_timestamp(2592000000,'PST') and from_utc_timestamp(timestamp '1970-01-30 16:00:00','PST') all return the timestamp 1970-01-30 08:00:00.

Source codeGenericUDFFromUtcTimestamp

timestamp

to_utc_timestamp({any primitive type} ts, string timezone)

Converts a timestamp* in a given timezone to UTC.

* timestamp is a primitive type, including timestamp/date, tinyint/smallint/int/bigint, float/double and decimal.

Fractional values are considered as seconds. Integer values are considered as milliseconds. For example, to_utc_timestamp(2592000.0,'PST'), to_utc_timestamp(2592000000,'PST') and to_utc_timestamp(timestamp '1970-01-30 16:00:00','PST') all return the timestamp 1970-01-31 00:00:00.

Source codeGenericUDFToUtcTimestamp

datecurrent_date

Returns the current date at the start of query evaluation. All calls of current_date within the same query return the same value.

Source codeGenericUDFCurrentDate

timestampcurrent_timestamp

Returns the current timestamp at the start of query evaluation. All calls of current_timestamp within the same query return the same value.

Source codeGenericUDFCurrentTimestamp

stringadd_months(string start_date, int num_months, output_date_format)

Returns the date that is num_months after start_date. start_date is a string, date or timestamp. num_months is an integer. If start_date is the last day of the month or if the resulting month has fewer days than the day component of start_date, then the result is the last day of the resulting month. Otherwise, the result has the same day component as start_date. The default output format is 'yyyy-MM-dd'.

Status
colourGreen
titleNew

Before Hive 4.0.0, the time part of the date is ignored. As of Hive 4.0.0, add_months supports an optional argument output_date_format, which accepts a String that represents a valid date format for the output. This allows to retain the time format in the output.

For example :

add_months('2009-08-31', 1) returns '2009-09-30'.
add_months('2017-12-31 14:15:16', 2, 'YYYY-MM-dd HH:mm:ss') returns '2018-02-28 14:15:16'.

Source codeGenericUDFAddMonths

stringlast_day(string date)Returns the last day of the month to which the date belongs. date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. The time part of the date is ignored!Source codeGenericUDFLastDay
stringnext_day(string start_date, string day_of_week)Returns the first date which is later than start_date and named as day_of_week.  start_date  is a string/date/timestamp. day_of_week is 2 letters, 3 letters or full name of the day of the week (e.g. Mo, tue, FRIDAY). The time part of start_date is ignored. Example: next_day('2015-01-14', 'TU') = 2015-01-20.Source codeGenericUDFNextDay
stringtrunc(string date, string format)Returns date truncated to the unit specified by the format. Supported formats: MONTH/MON/MM, YEAR/YYYY/YY. Example: trunc('2015-03-17', 'MM') = 2015-03-01.Source codeGenericUDFTrunc
doublemonths_between(date1, date2)Returns the number of months between dates date1 and date2. If date1 is later than date2, then the result is positive. If date1 is earlier than date , then the result is negative. If date1 and date2 are either the same days of the month or both last days of months, then the result is always an integer. Otherwise, the UDF calculates the fractional portion of the result based on a 31-day month and considers the difference in time components date1 and date2. date1 and date2 type can be date, timestamp or string in the format 'yyyy-MM-dd' or 'yyyy-MM-dd HH:mm:ss'. The result is rounded to 8 decimal places. Example: months_between('1997-02-28 10:30:00', '1996-10-30') = 3.94959677Source codeGenericUDFMonthsBetween
stringdate_format(date/timestamp/string ts, string pattern)

Converts a date/timestamp/string to a value of string using the specified pattern. The accepted patterns and their behavior depend on the underlying formatter implementation. The pattern argument should be constant. Example: date_format('2015-04-08', 'y') = '2015'.

date_format can be used to implement other UDFs, e.g.:

  • dayname(date) is date_format(date, 'EEEE')
  • dayofyear(date) is date_format(date, 'D')

Status
colourGreen
titleNew

As of Hive 4.0.0 the "hive.datetime.formatter" property can be used to control the underlying formatter implementation and as a consequence the accepted patterns and their behavior.  Earlier versions used https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html as the underlying formatter.

Source codeGenericUDFDateFormat

Mathematical Functions

The following built-in mathematical functions are supported in Hive. 

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The following built-in type conversion functions are supported in Hive. 

Return Type

Name(Signature)

Description

OSS

binary

binary(string|binary)

Casts the parameter into a binary.

GenericUDFBaseBinary

Expected "=" to follow "type"

cast(expr as <type>)

Converts the results of the expression expr to <type>. For example, cast('1' as BIGINT) will convert the string '1' to its integral representation. A null is returned if the conversion does not succeed. If cast(expr as boolean) Hive returns true for a non-empty string.


Conditional Functions

The following built-in conditional functions are supported in Hive.

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