HIVE全部函数详解

2017-09-13 18:04 出处:csdn 人气: 评论(0
函数名含义及实例absabs(x) - returns the absolute value of x
Example:
  > SELECT abs(0) FROM src LIMIT 1;
  0
  > SELECT abs(-5) FROM src LIMIT 1;
  5acosacos(x) - returns the arc cosine of x if -1<=x<=1 or NULL otherwise
Example:
  > SELECT acos(1) FROM src LIMIT 1;
  0
  > SELECT acos(2) FROM src LIMIT 1;add_monthsadd_months(start_date, num_months) - Returns the date that is num_months after start_date.
start_date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. num_months is a number. The time part of start_date is ignored.
Example:
  > SELECT add_months('2009-08-31', 1) FROM src LIMIT 1;
 '2009-09-30'aes_decryptaes_decrypt(input binary, key string/binary) - Decrypt input using AES.
AES (Advanced Encryption Standard) algorithm. Key lengths of 128, 192 or 256 bits can be used. 192 and 256 bits keys can be used if Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files are installed. If either argument is NULL or the key length is not one of the permitted values, the return value is NULL.
Example: > SELECT aes_decrypt(unbase64('y6Ss+zCYObpCbgfWfyNWTw=='), '1234567890123456');
 'ABC'aes_encryptaes_encrypt(input string/binary, key string/binary) - Encrypt input using AES.
AES (Advanced Encryption Standard) algorithm. Key lengths of 128, 192 or 256 bits can be used. 192 and 256 bits keys can be used if Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files are installed. If either argument is NULL or the key length is not one of the permitted values, the return value is NULL.
Example: > SELECT base64(aes_encrypt('ABC', '1234567890123456'));
 'y6Ss+zCYObpCbgfWfyNWTw=='anda1 and a2 and ... and an - Logical andarrayarray(n0, n1...) - Creates an array with the given elements array_containsarray_contains(array, value) - Returns TRUE if the array contains value.
Example:
  > SELECT array_contains(array(1, 2, 3), 2) FROM src LIMIT 1;
  trueasciiascii(str) - returns the numeric value of the first character of str
Returns 0 if str is empty or NULL if str is NULL
Example:
  > SELECT ascii('222') FROM src LIMIT 1;  50
  > SELECT ascii(2) FROM src LIMIT 1;
  50asinasin(x) - returns the arc sine of x if -1<=x<=1 or NULL otherwise
Example:
  > SELECT asin(0) FROM src LIMIT 1;
  0
  > SELECT asin(2) FROM src LIMIT 1;
  NULLassert_trueassert_true(condition) - Throw an exception if 'condition' is not true.
Example:
   > SELECT assert_true(x >= 0) FROM src LIMIT 1;
  NULLatanatan(x) - returns the atan (arctan) of x (x is in radians)
Example:
   > SELECT atan(0) FROM src LIMIT 1;
  0avgavg(x) - Returns the mean of a set of numbersbase64base64(bin) - Convert the argument from binary to a base 64 stringbetweenbetween a [NOT] BETWEEN b AND c - evaluate if a is [not] in between b and cbinbin(n) - returns n in binary
n is a BIGINT. Returns NULL if n is NULL.
Example:
  > SELECT bin(13) FROM src LIMIT 1
  '1101'bloom_filterThere is no documentation for function 'bloom_filter'broundbround(x[, d]) - round x to d decimal places using HALF_EVEN rounding mode.
Banker's rounding. The value is rounded to the nearest even number. Also known as Gaussian rounding.
Example:
  > SELECT bround(12.25, 1);
  12.2cardinality_violationcardinality_violation(n0, n1...) - raises Cardinality ViolationcaseCASE a WHEN b THEN c [WHEN d THEN e]* [ELSE f] END - When a = b, returns c; when a = d, return e; else return f
Example:
 SELECT
 CASE deptno
   WHEN 1 THEN Engineering
   WHEN 2 THEN Finance
   ELSE admin
 END,
 CASE zone
   WHEN 7 THEN Americas
   ELSE Asia-Pac
 END
 FROM emp_detailscbrtcbrt(double) - Returns the cube root of a double value.
Example:
 > SELECT cbrt(27.0);
 3.0ceilceil(x) - Find the smallest integer not smaller than x
Synonyms: ceiling
Example:
  > SELECT ceil(-0.1) FROM src LIMIT 1;
  0
  > SELECT ceil(5) FROM src LIMIT 1;
  5ceilingceiling(x) - Find the smallest integer not smaller than x
Synonyms: ceil
Example:
  > SELECT ceiling(-0.1) FROM src LIMIT 1;
  0
  > SELECT ceiling(5) FROM src LIMIT 1;
  5char_lengthchar_length(str | binary) - Returns the number of characters in str or binary data
Synonyms: character_length
Example:
  > SELECT char_length('HUX81') FROM src LIMIT 1;
  5character_lengthcharacter_length(str | binary) - Returns the number of characters in str or binary data
Synonyms: char_length
Example:
  > SELECT character_length('HUX81') FROM src LIMIT 1;
  5chrchr(str) - convert n where n : [0, 256) into the ascii equivalent as a varchar.If n is less than 0 return the empty string. If n > 256, return chr(n % 256).
Example:
  > SELECT chr('48') FROM src LIMIT 1;
  '0'
  > SELECT chr('65') FROM src LIMIT 1;
  'A'coalescecoalesce(a1, a2, ...) - Returns the first non-null argument
Example:
  > SELECT coalesce(NULL, 1, NULL) FROM src LIMIT 1;
  1collect_listcollect_list(x) - Returns a list of objects with duplicatescollect_setcollect_set(x) - Returns a set of objects with duplicate elements eliminatedcompute_statscompute_stats(x) - Returns the statistical summary of a set of primitive type values.concatconcat(str1, str2, ... strN) - returns the concatenation of str1, str2, ... strN or concat(bin1, bin2, ... binN) - returns the concatenation of bytes in binary data  bin1, bin2, ... binN
Returns NULL if any argument is NULL.
Example:
  > SELECT concat('abc', 'def') FROM src LIMIT 1;
  'abcdef'concat_wsconcat_ws(separator, [string | array(string)]+) - returns the concatenation of the strings separated by the separator.
Example:
  > SELECT concat_ws('.', 'www', array('facebook', 'com')) FROM src LIMIT 1;
  'www.facebook.com'context_ngramscontext_ngrams(expr, array<string1, string2, ...>, k, pf) estimates the top-k most frequent n-grams that fit into the specified context. The second parameter specifies a string of words that specify the positions of the n-gram elements, with a null value standing in for a 'blank' that must be filled by an n-gram element.
The primary expression must be an array of strings, or an array of arrays of strings, such as the return type of the sentences() UDF. The second parameter specifies the context -- for example, array("i", "love", null) -- which would estimate the top 'k' words that follow the phrase "i love" in the primary expression. The optional fourth parameter 'pf' controls the memory used by the heuristic. Larger values will yield better accuracy, but use more memory. Example usage:
  SELECT context_ngrams(sentences(lower(review)), array("i", "love", null, null), 10) FROM movies
would attempt to determine the 10 most common two-word phrases that follow "i love" in a database of free-form natural language movie reviews.convconv(num, from_base, to_base) - convert num from from_base to to_base
If to_base is negative, treat num as a signed integer,otherwise, treat it as an unsigned integer.
Example:
  > SELECT conv('100', 2, 10) FROM src LIMIT 1;
  '4'
  > SELECT conv(-10, 16, -10) FROM src LIMIT 1;
  '16'corrcorr(y,x) - Returns the Pearson coefficient of correlation
between a set of number pairs
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If N*SUM(x*x) = SUM(x)*SUM(x): NULL is returned.
If N*SUM(y*y) = SUM(y)*SUM(y): NULL is returned.
Otherwise, it computes the following:
   COVAR_POP(x,y)/(STDDEV_POP(x)*STDDEV_POP(y))
where neither x nor y is null,
COVAR_POP is the population covariance,
and STDDEV_POP is the population standard deviation.coscos(x) - returns the cosine of x (x is in radians)
Example:
   > SELECT cos(0) FROM src LIMIT 1;
  1countcount(*) - 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.covar_popcovar_pop(x,y) - Returns the population covariance of a set of number pairs
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored. If the function is applied to an empty set, NULL
will be returned. Otherwise, it computes the following:
   (SUM(x*y)-SUM(x)*SUM(y)/COUNT(x,y))/COUNT(x,y)
where neither x nor y is null.covar_sampcovar_samp(x,y) - Returns the sample covariance of a set of number pairs
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If applied to a set with a single element: NULL is returned.
Otherwise, it computes the following:
   (SUM(x*y)-SUM(x)*SUM(y)/COUNT(x,y))/(COUNT(x,y)-1)
where neither x nor y is null.
1crc32crc32(str or bin) - Computes a cyclic redundancy check value for string or binary argument and returns bigint value.
Example:
  > SELECT crc32('ABC');
  2743272264
  > SELECT crc32(binary('ABC'));
  2743272264create_unioncreate_union(tag, obj1, obj2, obj3, ...) - Creates a union with the object for given tag
Example:
  > SELECT create_union(1, 1, "one") FROM src LIMIT 1;
  onecume_distThere is no documentation for function 'cume_dist'current_databasecurrent_database() - returns currently using database namecurrent_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.current_timestampcurrent_timestamp() - Returns the current timestamp at the start of query evaluation. All calls of current_timestamp within the same query return the same valuecurrent_usercurrent_user() - Returns current user namedate_adddate_add(start_date, num_days) - Returns the date that is num_days after start_date.
start_date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. num_days is a number. The time part of start_date is ignored.
Example:
   > SELECT date_add('2009-07-30', 1) FROM src LIMIT 1;
  '2009-07-31'date_formatdate_format(date/timestamp/string, fmt) - converts a date/timestamp/string to a value of string in the format specified by the date format fmt.
Supported formats are SimpleDateFormat formats - https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html. Second argument fmt should be constant.
Example: > SELECT date_format('2015-04-08', 'y');
 '2015'date_subdate_sub(start_date, num_days) - Returns the date that is num_days before start_date.
start_date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. num_days is a number. The time part of start_date is ignored.
Example:
   > SELECT date_sub('2009-07-30', 1) FROM src LIMIT 1;
  '2009-07-29'datediffdatediff(date1, date2) - Returns the number of days between date1 and date2
date1 and date2 are strings in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. The time parts are ignored.If date1 is earlier than date2, the result is negative.
Example:
   > SELECT datediff('2009-07-30', '2009-07-31') FROM src LIMIT 1;
  1dayday(param) - Returns the day of the month of date/timestamp, or day component of interval
Synonyms: dayofmonth
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.
2. A date value
3. A timestamp value
4. A day-time interval valueExample:
   > SELECT day('2009-07-30') FROM src LIMIT 1;
  30dayofmonthdayofmonth(param) - Returns the day of the month of date/timestamp, or day component of interval
Synonyms: day
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.
2. A date value
3. A timestamp value
4. A day-time interval valueExample:
   > SELECT dayofmonth('2009-07-30') FROM src LIMIT 1;
  30dayofweekdayofweek(param) - Returns the day of the week of date/timestamp (1 = Sunday, 2 = Monday, ..., 7 = Saturday)
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.
2. A date value
3. A timestamp valueExample:
   > SELECT dayofweek('2009-07-30') FROM src LIMIT 1;
  5decodedecode(bin, str) - Decode the first argument using the second argument character set
Possible options for the character set are 'US-ASCII', 'ISO-8859-1',
'UTF-8', 'UTF-16BE', 'UTF-16LE', and 'UTF-16'. If either argument
is null, the result will also be nulldegreesdegrees(x) - Converts radians to degrees
Example:
  > SELECT degrees(30) FROM src LIMIT 1;
  -1dense_rankThere is no documentation for function 'dense_rank'diva div b - Divide a by b rounded to the long integer
Example:
  > SELECT 3 div 2 FROM src LIMIT 1;
  1ee() - returns E
Example:
 > SELECT e() FROM src LIMIT 1;
 2.718281828459045eltelt(n, str1, str2, ...) - returns the n-th string
Example:
  > SELECT elt(1, 'face', 'book') FROM src LIMIT 1;
  'face'encodeencode(str, str) - Encode the first argument using the second argument character set
Possible options for the character set are 'US-ASCII', 'ISO-8859-1',
'UTF-8', 'UTF-16BE', 'UTF-16LE', and 'UTF-16'. If either argument
is null, the result will also be nullewah_bitmapewah_bitmap(expr) - Returns an EWAH-compressed bitmap representation of a column.ewah_bitmap_andewah_bitmap_and(b1, b2) - Return an EWAH-compressed bitmap that is the bitwise AND of two bitmaps.ewah_bitmap_emptyewah_bitmap_empty(bitmap) - Predicate that tests whether an EWAH-compressed bitmap is all zerosewah_bitmap_orewah_bitmap_or(b1, b2) - Return an EWAH-compressed bitmap that is the bitwise OR of two bitmaps.expexp(x) - Returns e to the power of x
Example:
   > SELECT exp(0) FROM src LIMIT 1;
  1explodeexplode(a) - separates the elements of array a into multiple rows, or the elements of a map into multiple rows and columnsextract_unionextract_union(union[, tag]) - Recursively explodes unions into structs or simply extracts the given tag.
  > SELECT extract_union({0:"foo"}).tag_0 FROM src;
  foo
  > SELECT extract_union({0:"foo"}).tag_1 FROM src;
  null
  > SELECT extract_union({0:"foo"}, 0) FROM src;
  foo
  > SELECT extract_union({0:"foo"}, 1) FROM src;
  nullfactorialfactorial(int) - Returns n factorial. Valid n is [0..20].
Returns null if n is out of [0..20] range.
Example:
 > SELECT factorial(5);
 120fieldfield(str, str1, str2, ...) - returns the index of str in the str1,str2,... list or 0 if not found
All primitive types are supported, arguments are compared using str.equals(x). If str is NULL, the return value is 0.find_in_setfind_in_set(str,str_array) - Returns the first occurrence  of str in str_array where str_array is a comma-delimited string. Returns null if either argument is null. Returns 0 if the first argument has any commas.
Example:
  > SELECT find_in_set('ab','abc,b,ab,c,def') FROM src LIMIT 1;
  3
  > SELECT * FROM src1 WHERE NOT find_in_set(key,'311,128,345,956')=0;
  311  val_311
  128first_valueThere is no documentation for function 'first_value'floorfloor(x) - Find the largest integer not greater than x
Example:
  > SELECT floor(-0.1) FROM src LIMIT 1;
  -1
  > SELECT floor(5) FROM src LIMIT 1;
  5floor_dayfloor_day(param) - Returns the timestamp at a day granularity
param needs to be a timestamp value
Example:
   > SELECT floor_day(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-dd 00:00:00floor_hourfloor_hour(param) - Returns the timestamp at a hour granularity
param needs to be a timestamp value
Example:
   > SELECT floor_hour(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-dd HH:00:00floor_minutefloor_minute(param) - Returns the timestamp at a minute granularity
param needs to be a timestamp value
Example:
   > SELECT floor_minute(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-dd HH:mm:00floor_monthfloor_month(param) - Returns the timestamp at a month granularity
param needs to be a timestamp value
Example:
   > SELECT floor_month(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-01 00:00:00floor_quarterfloor_quarter(param) - Returns the timestamp at a quarter granularity
param needs to be a timestamp value
Example:
   > SELECT floor_quarter(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-xx-01 00:00:00
5floor_secondfloor_second(param) - Returns the timestamp at a second granularity
param needs to be a timestamp value
Example:
   > SELECT floor_second(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-dd HH:mm:ssfloor_weekfloor_week(param) - Returns the timestamp at a week granularity
param needs to be a timestamp value
Example:
   > SELECT floor_week(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-MM-xx 00:00:00floor_yearfloor_year(param) - Returns the timestamp at a year granularity
param needs to be a timestamp value
Example:
   > SELECT floor_year(CAST('yyyy-MM-dd HH:mm:ss' AS TIMESTAMP)) FROM src;
  yyyy-01-01 00:00:00format_numberformat_number(X, D or F) - Formats the number X to a format like '#,###,###.##', rounded to D decimal places, Or Uses the format specified F to format, and returns the result as a string. If D is 0, the result has no decimal point or fractional part. This is supposed to function like MySQL's FORMAT
Example:
  > SELECT format_number(12332.123456, 4) FROM src LIMIT 1;
  '12,332.1235'
  > SELECT format_number(12332.123456, '##################.###') FROM src LIMIT 1;
  '12332.123'from_unixtimefrom_unixtime(unix_time, format) - returns unix_time in the specified format
Example:
  > SELECT from_unixtime(0, 'yyyy-MM-dd HH:mm:ss') FROM src LIMIT 1;
  '1970-01-01 00:00:00'from_utc_timestampfrom_utc_timestamp(timestamp, string timezone) - Assumes given timestamp is UTC and converts to given timezone (as of Hive 0.8.0)get_json_objectget_json_object(json_txt, path) - Extract a json object from path
Extract json object from a json string based on json path specified, and return json string of the extracted json object. It will return null if the input json string is invalid.
A limited version of JSONPath supported:
  $   : Root object
  .   : Child operator
  []  : Subscript operator for array
  *   : Wildcard for []
Syntax not supported that's worth noticing:
  ''  : Zero length string as key
  ..  : Recursive descent
  &amp;#064;   : Current object/element
  ()  : Script expression
  ?() : Filter (script) expression.
  [,] : Union operator
  [start:end:step] : array slice operatorget_splitsget_splits(string,int) - Returns an array of length int serialized splits for the referenced tables string.greatestgreatest(v1, v2, ...) - Returns the greatest value in a list of values
Example:
  > SELECT greatest(2, 3, 1) FROM src LIMIT 1;
  3groupinggrouping(a, b) - Indicates whether a specified column expression in is aggregated or not. Returns 1 for aggregated or 0 for not aggregated.
a is the grouping id, b is the index we want to extracthashhash(a1, a2, ...) - Returns a hash value of the argumentshexhex(n, bin, or str) - Convert the argument to hexadecimal
If the argument is a string, returns two hex digits for each character in the string.
If the argument is a number or binary, returns the hexadecimal representation.
Example:
  > SELECT hex(17) FROM src LIMIT 1;
  'H1'
  > SELECT hex('Facebook') FROM src LIMIT 1;
  '46616365626F6F6B'histogram_numerichistogram_numeric(expr, nb) - Computes a histogram on numeric 'expr' using nb bins.
Example:
> SELECT histogram_numeric(val, 3) FROM src;
[{"x":100,"y":14.0},{"x":200,"y":22.0},{"x":290.5,"y":11.0}]
The return value is an array of (x,y) pairs representing the centers of the histogram's bins. As the value of 'nb' is increased, the histogram approximationgets finer-grained, but may yield artifacts around outliers. In practice, 20-40 histogram bins appear to work well, with more bins being required for skewed or smaller datasets. Note that this function creates a histogram with non-uniform bin widths. It offers no guarantees in terms of the mean-squared-error of the histogram, but in practice is comparable to the histograms produced by the R/S-Plusstatistical computing packages.hourhour(param) - Returns the hour componemnt of the string/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'HH:mm:ss'.
2. A timestamp value
3. A day-time interval valueExample:
   > SELECT hour('2009-07-30 12:58:59') FROM src LIMIT 1;
  12
  > SELECT hour('12:58:59') FROM src LIMIT 1;
  12ifIF(expr1,expr2,expr3) - If expr1 is TRUE (expr1 <> 0 and expr1 <> NULL) then IF() returns expr2; otherwise it returns expr3. IF() returns a numeric or string value, depending on the context in which it is used.intest in(val1, val2...) - returns true if test equals any valNin_bloom_filterin_filein_file(str, filename) - Returns true if str appears in the fileindexindex(a, n) - Returns the n-th element of ainitcapinitcap(str) - Returns str, with the first letter of each word in uppercase, all other letters in lowercase. Words are delimited by white space.
Example:
 > SELECT initcap('tHe soap') FROM src LIMIT 1;
 'The Soap'inlineinline( ARRAY( STRUCT()[,STRUCT()] - explodes and array and struct into a tableinstrinstr(str, substr) - Returns the index of the first occurance of substr in str
Example:
  > SELECT instr('Facebook', 'boo') FROM src LIMIT 1;
  5internal_intervalinternal_interval(intervalType,intervalArg)
this method is not designed to be used by directly calling it - it provides internal support for 'INTERVAL (intervalArg) intervalType' constructsisnotnullisnotnull a - Returns true if a is not NULL and false otherwiseisnullisnull a - Returns true if a is NULL and false otherwisejava_methodjava_method(class,method[,arg1[,arg2..]]) calls method with reflection
Synonyms: reflect
Use this UDF to call Java methods by matching the argument signaturejson_tuplejson_tuple(jsonStr, p1, p2, ..., pn) - like get_json_object, but it takes multiple names and return a tuple. All the input parameters and output column types are string.
Function class:org.apache.hadoop.hive.ql.udf.generic.GenericUDTFJSONTuplelagLAG  (scalar_expression [,offset] [,default]) OVER ([query_partition_clause] order_by_clause); The LAG function is used to access data from a previous row.
Example:
 select p1.p_mfgr, p1.p_name, p1.p_size,
 p1.p_size - lag(p1.p_size,1,p1.p_size) over( distribute by p1.p_mfgr sort by p1.p_name) as deltaSz
 from part p1 join part p2 on p1.p_partkey = p2.p_partkeylast_daylast_day(date) - Returns the last day of the month which the date belongs to.
date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. The time part of date is ignored.
Example:
  > SELECT last_day('2009-01-12') FROM src LIMIT 1;
 '2009-01-31'last_valuelcaselcase(str) - Returns str with all characters changed to lowercase
Synonyms: lower
Example:
  > SELECT lcase('Facebook') FROM src LIMIT 1;
  'facebook'leadLEAD (scalar_expression [,offset] [,default]) OVER ([query_partition_clause] order_by_clause); The LEAD function is used to return data from the next row.
Example:
 select p_name, p_retailprice, lead(p_retailprice) over() as l1,
 lag(p_retailprice) over() as l2
 from part
 where p_retailprice = 1173.15leastleast(v1, v2, ...) - Returns the least value in a list of values
Example:
  > SELECT least(2, 3, 1) FROM src LIMIT 1;
  1lengthlength(str | binary) - Returns the length of str or number of bytes in binary data
Example:
  > SELECT length('Facebook') FROM src LIMIT 1;
  8levenshteinlevenshtein(str1, str2) - This function calculates the Levenshtein distance between two strings.
Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein distance between two words is the minimum number of single-character edits (i.e. insertions, deletions or substitutions) required to change one word into the other. It is named after Vladimir Levenshtein, who considered this distance in 1965.Example:
  > SELECT levenshtein('kitten', 'sitting');
 3likelike(str, pattern) - Checks if str matches pattern
Example:
  > SELECT a.* FROM srcpart a WHERE a.hr like '%2' LIMIT 1;
  27      val_27  2008-04-08      12lnln(x) - Returns the natural logarithm of x
Example:
  > SELECT ln(1) FROM src LIMIT 1;
  0locatelocate(substr, str[, pos]) - Returns the position of the first occurance of substr in str after position pos
Example:
  > SELECT locate('bar', 'foobarbar', 5) FROM src LIMIT 1;
  7loglog([b], x) - Returns the logarithm of x with base b
Example:
  > SELECT log(13, 13) FROM src LIMIT 1;
  1log10log10(x) - Returns the logarithm of x with base 10
Example:
  > SELECT log10(10) FROM src LIMIT 1;
  1log2log2(x) - Returns the logarithm of x with base 2
Example:
  > SELECT log2(2) FROM src LIMIT 1;
  1logged_in_userlogged_in_user() - Returns logged in user name
SessionState GetUserName - the username provided at session initializationlowerlower(str) - Returns str with all characters changed to lowercase
Synonyms: lcase
Example:
  > SELECT lower('Facebook') FROM src LIMIT 1;
  'facebook'lpadlpad(str, len, 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.
Example:
  > SELECT lpad('hi', 5, '??') FROM src LIMIT 1;
  '???hi'
  > SELECT lpad('hi', 1, '??') FROM src LIMIT 1;
  'h'
  > SELECT lpad('hi', 5, '') FROM src LIMIT 1;
  nullltrimltrim(str) - Removes the leading space characters from str
Example:
  > SELECT ltrim('   facebook') FROM src LIMIT 1;
  'facebook'mapmap(key0, value0, key1, value1...) - Creates a map with the given key/value pairs map_keysmap_keys(map) - Returns an unordered array containing the keys of the input mapmap_valuesmap_values(map) - Returns an unordered array containing the values of the input map.maskmasks the given value
Examples:
   mask(ccn)
   mask(ccn, 'X', 'x', '0')
   mask(ccn, 'x', 'x', 'x')
 Arguments:
   mask(value, upperChar, lowerChar, digitChar, otherChar, numberChar, dayValue, monthValue, yearValue)
     value      - value to mask. Supported types: TINYINT, SMALLINT, INT, BIGINT, STRING, VARCHAR, CHAR, DATE
     upperChar  - character to replace upper-case characters with. Specify -1 to retain original character. Default value: 'X'
     lowerChar  - character to replace lower-case characters with. Specify -1 to retain original character. Default value: 'x'
     digitChar  - character to replace digit characters with. Specify -1 to retain original character. Default value: 'n'
     otherChar  - character to replace all other characters with. Specify -1 to retain original character. Default value: -1
     numberChar - character to replace digits in a number with. Valid values: 0-9. Default value: '1'
     dayValue   - value to replace day field in a date with.  Specify -1 to retain original value. Valid values: 1-31. Default value: 1
     monthValue - value to replace month field in a date with. Specify -1 to retain original value. Valid values: 0-11. Default value: 0
     yearValue  - value to replace year field in a date with. Specify -1 to retain original value. Default value: 0mask_first_nmasks the first n characters of the value
Examples:
   mask_first_n(ccn, 8)
   mask_first_n(ccn, 8, 'x', 'x', 'x')
 Arguments:
   mask(value, charCount, upperChar, lowerChar, digitChar, otherChar, numberChar)
     value      - value to mask. Supported types: TINYINT, SMALLINT, INT, BIGINT, STRING, VARCHAR, CHAR
     charCount  - number of characters. Default value: 4
     upperChar  - character to replace upper-case characters with. Specify -1 to retain original character. Default value: 'X'
     lowerChar  - character to replace lower-case characters with. Specify -1 to retain original character. Default value: 'x'
     digitChar  - character to replace digit characters with. Specify -1 to retain original character. Default value: 'n'
     otherChar  - character to replace all other characters with. Specify -1 to retain original character. Default value: -1
     numberChar - character to replace digits in a number with. Valid values: 0-9. Default value: '1'mask_hashreturns hash of the given value
Examples:
   mask_hash(value)
 Arguments:
   value - value to mask. Supported types: STRING, VARCHAR, CHARmask_last_nmasks the last n characters of the value
Examples:
   mask_last_n(ccn, 8)
   mask_last_n(ccn, 8, 'x', 'x', 'x')
 Arguments:
   mask_last_n(value, charCount, upperChar, lowerChar, digitChar, otherChar, numberChar)
     value      - value to mask. Supported types: TINYINT, SMALLINT, INT, BIGINT, STRING, VARCHAR, CHAR
     charCount  - number of characters. Default value: 4
     upperChar  - character to replace upper-case characters with. Specify -1 to retain original character. Default value: 'X'
     lowerChar  - character to replace lower-case characters with. Specify -1 to retain original character. Default value: 'x'
     digitChar  - character to replace digit characters with. Specify -1 to retain original character. Default value: 'n'
     otherChar  - character to replace all other characters with. Specify -1 to retain original character. Default value: -1
      numberChar - character to replace digits in a number with. Valid values: 0-9. Default value: '1'mask_show_first_nmasks all but first n characters of the value
Examples:
   mask_show_first_n(ccn, 8)
   mask_show_first_n(ccn, 8, 'x', 'x', 'x')
 Arguments:
   mask_show_first_n(value, charCount, upperChar, lowerChar, digitChar, otherChar, numberChar)
     value      - value to mask. Supported types: TINYINT, SMALLINT, INT, BIGINT, STRING, VARCHAR, CHAR
     charCount  - number of characters. Default value: 4
     upperChar  - character to replace upper-case characters with. Specify -1 to retain original character. Default value: 'X'
     lowerChar  - character to replace lower-case characters with. Specify -1 to retain original character. Default value: 'x'
     digitChar  - character to replace digit characters with. Specify -1 to retain original character. Default value: 'n'
     otherChar  - character to replace all other characters with. Specify -1 to retain original character. Default value: -1
     numberChar - character to replace digits in a number with. Valid values: 0-9. Default value: '1'mask_show_last_nmasks all but last n characters of the value
Examples:
   mask_show_last_n(ccn, 8)
   mask_show_last_n(ccn, 8, 'x', 'x', 'x')
 Arguments:
   mask_show_last_n(value, charCount, upperChar, lowerChar, digitChar, otherChar, numberChar)
     value      - value to mask. Supported types: TINYINT, SMALLINT, INT, BIGINT, STRING, VARCHAR, CHAR
     charCount  - number of characters. Default value: 4
     upperChar  - character to replace upper-case characters with. Specify -1 to retain original character. Default value: 'X'
     lowerChar  - character to replace lower-case characters with. Specify -1 to retain original character. Default value: 'x'
     digitChar  - character to replace digit characters with. Specify -1 to retain original character. Default value: 'n'
     otherChar  - character to replace all other characters with. Specify -1 to retain original character. Default value: -1
     numberChar - character to replace digits in a number with. Valid values: 0-9. Default value: '1'matchpathmaxmax(expr) - Returns the maximum value of exprmd5md5(str or bin) - Calculates an MD5 128-bit checksum for the string or binary.
The value is returned as a string of 32 hex digits, or NULL if the argument was NULL.
Example:
  > SELECT md5('ABC');
  '902fbdd2b1df0c4f70b4a5d23525e932'
  > SELECT md5(binary('ABC'));
  '902fbdd2b1df0c4f70b4a5d23525e932'minmin(expr) - Returns the minimum value of exprminuteminute(param) - Returns the minute component of the string/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'HH:mm:ss'.
2. A timestamp value
3. A day-time interval valueExample:
   > SELECT minute('2009-07-30 12:58:59') FROM src LIMIT 1;
  58
  > SELECT minute('12:58:59') FROM src LIMIT 1;
  58moda mod b - Returns the remainder when dividing a by b
Synonyms: %monthmonth(param) - Returns the month component of the date/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.
2. A date value
3. A timestamp value
4. A year-month interval valueExample:
  > SELECT month('2009-07-30') FROM src LIMIT 1;
  7months_betweenmonths_between(date1, date2, roundOff) - returns number of months between dates date1 and date2
If date1 is later than date2, then the result is positive. If date1 is earlier than date2, 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 by default. Set roundOff=false otherwise.
 Example:
  > SELECT months_between('1997-02-28 10:30:00', '1996-10-30');
 3.94959677named_structnamed_struct(name1, val1, name2, val2, ...) - Creates a struct with the given field names and valuesnegativenegative a - Returns -anext_daynext_day(start_date, day_of_week) - Returns the first date which is later than start_date and named as indicated.
start_date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. day_of_week is day of the week (e.g. Mo, tue, FRIDAY).Example:
  > SELECT next_day('2015-01-14', 'TU') FROM src LIMIT 1;
 '2015-01-20'ngramsngrams(expr, n, k, pf) - Estimates the top-k n-grams in rows that consist of sequences of strings, represented as arrays of strings, or arrays of arrays of strings. 'pf' is an optional precision factor that controls memory usage.
The parameter 'n' specifies what type of n-grams are being estimated. Unigrams are n = 1, and bigrams are n = 2. Generally, n will not be greater than about 5. The 'k' parameter specifies how many of the highest-frequency n-grams will be returned by the UDAF. The optional precision factor 'pf' specifies how much memory to use for estimation; more memory will give more accurate frequency counts, but could crash the JVM. The default value is 20, which internally maintains 20*k n-grams, but only returns the k highest frequency ones. The output is an array of structs with the top-k n-grams. It might be convenient to explode() the output of this UDAF.noopnoopstreamingnoopwithmapnoopwithmapstreamingnotnot a - Logical not Synonyms: !ntilenullifSELECT nullif(1,1),nullif(1,2)nvlnvl(value,default_value) - Returns default value if value is null else returns value
Example:
  > SELECT nvl(null,'bla') FROM src LIMIT 1;
  blaoctet_lengthoctet_length(str | binary) - Returns the number of bytes in str or binary data
Example:
  > SELECT octet_length('HUX8�') FROM src LIMIT 1;
  15ora1 or a2 or ... or an - Logical orparse_urlparse_url(url, partToExtract[, key]) - extracts a part from a URL
Parts: HOST, PATH, QUERY, REF, PROTOCOL, AUTHORITY, FILE, USERINFO
key specifies which query to extract
Example:
  > SELECT parse_url('http://facebook.com/path/p1.php?query=1', 'HOST') FROM src LIMIT 1;
  'facebook.com'
  > SELECT parse_url('http://facebook.com/path/p1.php?query=1', 'QUERY') FROM src LIMIT 1;
  'query=1'
  > SELECT parse_url('http://facebook.com/path/p1.php?query=1', 'QUERY', 'query') FROM src LIMIT 1;
  '1'parse_url_tupleparse_url_tuple(url, partname1, partname2, ..., partnameN) - extracts N (N>=1) parts from a URL.
It takes a URL and one or multiple partnames, and returns a tuple. All the input parameters and output column types are string.
Partname: HOST, PATH, QUERY, REF, PROTOCOL, AUTHORITY, FILE, USERINFO, QUERY:<KEY_NAME>
Note: Partnames are case-sensitive, and should not contain unnecessary white spaces.
Example:
  > SELECT b.* FROM src LATERAL VIEW parse_url_tuple(fullurl, 'HOST', 'PATH', 'QUERY', 'QUERY:id') b as host, path, query, query_id LIMIT 1;
  > SELECT parse_url_tuple(a.fullurl, 'HOST', 'PATH', 'QUERY', 'REF', 'PROTOCOL', 'FILE',  'AUTHORITY', 'USERINFO', 'QUERY:k1') as (ho, pa, qu, re, pr, fi, au, us, qk1) from src a;percent_rankpercentilepercentile(expr, pc) - Returns the percentile(s) of expr at pc (range: [0,1]).pc can be a double or double arraypercentile_approxpercentile_approx(expr, pc, [nb]) - For very large data, computes an approximate percentile value from a histogram, using the optional argument [nb] as the number of histogram bins to use. A higher value of nb results in a more accurate approximation, at the cost of higher memory usage.
'expr' can be any numeric column, including doubles and floats, and 'pc' is either a single double/float with a requested percentile, or an array of double/float with multiple percentiles. If 'nb' is not specified, the default approximation is done with 10,000 histogram bins, which means that if there are 10,000 or fewer unique values in 'expr', you can expect an exact result. The percentile() function always computes an exact percentile and can run out of memory if there are too many unique values in a column, which necessitates this function.
Example (three percentiles requested using a finer histogram approximation):
> SELECT percentile_approx(val, array(0.5, 0.95, 0.98), 100000) FROM somedata;
[0.05,1.64,2.26]pipi() - returns pi
Example:
 > SELECT pi() FROM src LIMIT 1;
 3.14159...pmoda pmod b - Compute the positive moduloposexplodeposexplode(a) - behaves like explode for arrays, but includes the position of items in the original arraypositivepositive a - Returns apowpow(x1, x2) - raise x1 to the power of x2
Synonyms: power
Example:
  > SELECT pow(2, 3) FROM src LIMIT 1;
  8powerpower(x1, x2) - raise x1 to the power of x2
Synonyms: pow
Example:
  > SELECT power(2, 3) FROM src LIMIT 1;
  8printfprintf(String format, Obj... args) - function that can format strings according to printf-style format strings
Example:
  > SELECT printf("Hello World %d %s", 100, "days")FROM src LIMIT 1;
  "Hello World 100 days"quarterquarter(date/timestamp/string) - Returns the quarter of the year for date, in the range 1 to 4.
Example: > SELECT quarter('2015-04-08');
 2radiansradians(x) - Converts degrees to radians
Example:
  > SELECT radians(90) FROM src LIMIT 1;
  1.5707963267949morandrand([seed]) - Returns a pseudorandom number between 0 and 1rankreflectreflect(class,method[,arg1[,arg2..]]) calls method with reflection
Synonyms: java_method
Use this UDF to call Java methods by matching the argument signaturereflect2reflect2(arg0,method[,arg1[,arg2..]]) calls method of arg0 with reflection
Use this UDF to call Java methods by matching the argument signatureregexpstr regexp regexp - Returns true if str matches regexp and false otherwise
Synonyms: rlike
Example:
  > SELECT 'fb' regexp '.*' FROM src LIMIT 1;
  trueregexp_extractregexp_extract(str, regexp[, idx]) - extracts a group that matches regexp
Example:
  > SELECT regexp_extract('100-200', '(d+)-(d+)', 1) FROM src LIMIT 1;
  '100'regexp_replaceregexp_replace(str, regexp, rep) - replace all substrings of str that match regexp with rep
Example:
  > SELECT regexp_replace('100-200', '(d+)', 'num') FROM src LIMIT 1;
  'num-num'regr_avgxegr_avgx(y,x) - evaluates the average of the independent variable
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
Otherwise, it computes the following:
   AVG(X)regr_avgyregr_avgy(y,x) - evaluates the average of the dependent variable
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
Otherwise, it computes the following:
   AVG(Y)regr_countregr_count(y,x) - returns the number of non-null pairs
The function takes as arguments any pair of numeric types and returns a long.
Any pair with a NULL is ignored.regr_interceptregr_intercept(y,x) - returns the y-intercept of the regression line.
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If N*SUM(x*x) = SUM(x)*SUM(x): NULL is returned.
Otherwise, it computes the following:
   ( SUM(y)*SUM(x*x)-SUM(X)*SUM(x*y) )  /  ( N*SUM(x*x)-SUM(x)*SUM(x) )regr_r2regr_r2(y,x) - returns the coefficient of determination (also called R-squared or goodness of fit) for the regression line.
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If N*SUM(x*x) = SUM(x)*SUM(x): NULL is returned.
If N*SUM(y*y) = SUM(y)*SUM(y): 1 is returned.
Otherwise, it computes the following:
   POWER( N*SUM(x*y)-SUM(x)*SUM(y) ,2)  /  ( (N*SUM(x*x)-SUM(x)*SUM(x)) * (N*SUM(y*y)-SUM(y)*SUM(y)) )regr_sloperegr_slope(y,x) - returns the slope of the linear regression line
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If N*SUM(x*x) = SUM(x)*SUM(x): NULL is returned (the fit would be a vertical).
Otherwise, it computes the following:
   (N*SUM(x*y)-SUM(x)*SUM(y)) / (N*SUM(x*x)-SUM(x)*SUM(x))regr_sxxregr_sxx(y,x) - auxiliary analytic function
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
Otherwise, it computes the following:
   SUM(x*x)-SUM(x)*SUM(x)/Nregr_sxyregr_sxy(y,x) - return a value that can be used to evaluate the statistical validity of a regression model.
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
If N*SUM(x*x) = SUM(x)*SUM(x): NULL is returned.
Otherwise, it computes the following:
   SUM(x*y)-SUM(x)*SUM(y)/Nregr_syyregr_syy(y,x) - auxiliary analytic function
The function takes as arguments any pair of numeric types and returns a double.
Any pair with a NULL is ignored.
If applied to an empty set: NULL is returned.
Otherwise, it computes the following:
   SUM(y*y)-SUM(y)*SUM(y)/Nrepeatrepeat(str, n) - repeat str n times
Example:
  > SELECT repeat('123', 2) FROM src LIMIT 1;
  '123123'replacereplace(str, search, rep) - replace all substrings of 'str' that match 'search' with 'rep'
Example:
  > SELECT replace('Hack and Hue', 'H', 'BL') FROM src LIMIT 1;
  'BLack and BLue'replicate_rowsreplicate_rows(n, cols...) - turns 1 row into n rowsreversereverse(str) - reverse str
Example:
  > SELECT reverse('Facebook') FROM src LIMIT 1;
  'koobecaF'rlikestr rlike regexp - Returns true if str matches regexp and false otherwise
Synonyms: regexp
Example:
  > SELECT 'fb' rlike '.*' FROM src LIMIT 1;
  trueroundround(x[, d]) - round x to d decimal places
Example:
  > SELECT round(12.3456, 1) FROM src LIMIT 1;
  12.3'row_numberrpadrpad(str, len, 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.
Example:
  > SELECT rpad('hi', 5, '??') FROM src LIMIT 1;
  'hi???'
  > SELECT rpad('hi', 1, '??') FROM src LIMIT 1;
  'h'
  > SELECT rpad('hi', 5, '') FROM src LIMIT 1;
  nullrtrimrtrim(str) - Removes the trailing space characters from str
Example:
  > SELECT rtrim('facebook   ') FROM src LIMIT 1;
  'facebook'secondsecond(date) - Returns the second component of the string/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'HH:mm:ss'.
2. A timestamp value
3. A day-time interval valueExample:
   > SELECT second('2009-07-30 12:58:59') FROM src LIMIT 1;
  59
  > SELECT second('12:58:59') FROM src LIMIT 1;
  59sentencessentences(str, lang, country) - Splits str into arrays of sentences, where each sentence is an array of words. The 'lang' and'country' arguments are optional, and if omitted, the default locale is used.
Example:
  > SELECT sentences('Hello there! I am a UDF.') FROM src LIMIT 1;
  [ ["Hello", "there"], ["I", "am", "a", "UDF"] ]
  > SELECT sentences(review, language) FROM movies;
Unnecessary punctuation, such as periods and commas in English, is automatically stripped. If specified, 'lang' should be a two-letter ISO-639 language code (such as 'en'), and 'country' should be a two-letter ISO-3166 code (such as 'us'). Not all country and language codes are fully supported, and if an unsupported code is specified, a default locale is used to process that string.shasha(str or bin) - Calculates the SHA-1 digest for string or binary and returns the value as a hex string.
Synonyms: sha1
Example:
  > SELECT sha('ABC');
  '3c01bdbb26f358bab27f267924aa2c9a03fcfdb8'
  > SELECT sha(binary('ABC'));
  '3c01bdbb26f358bab27f267924aa2c9a03fcfdb8'sha1sha1(str or bin) - Calculates the SHA-1 digest for string or binary and returns the value as a hex string.
Synonyms: sha
Example:
  > SELECT sha1('ABC');
  '3c01bdbb26f358bab27f267924aa2c9a03fcfdb8'
  > SELECT sha1(binary('ABC'));
  '3c01bdbb26f358bab27f267924aa2c9a03fcfdb8'sha2sha2(string/binary, len) - Calculates the SHA-2 family of hash functions (SHA-224, SHA-256, SHA-384, and SHA-512).
The first argument is the string or binary to be hashed. The second argument indicates the desired bit length of the result, which must have a value of 224, 256, 384, 512, or 0 (which is equivalent to 256). SHA-224 is supported starting from Java 8. If either argument is NULL or the hash length is not one of the permitted values, the return value is NULL.
Example: > SELECT sha2('ABC', 256);
 'b5d4045c3f466fa91fe2cc6abe79232a1a57cdf104f7a26e716e0a1e2789df78'shiftleftshiftleft(a, b) - Bitwise left shift
Returns int for tinyint, smallint and int a. Returns bigint for bigint a.
Example:
  > SELECT shiftleft(2, 1);
  4shiftrightshiftright(a, b) - Bitwise right shift
Returns int for tinyint, smallint and int a. Returns bigint for bigint a.
Example:
  > SELECT shiftright(4, 1);
  2shiftrightunsignedshiftrightunsigned(a, b) - Bitwise unsigned right shift
Returns int for tinyint, smallint and int a. Returns bigint for bigint a.
Example:
  > SELECT shiftrightunsigned(4, 1);
  2signsign(x) - returns the sign of x )
Example:
   > SELECT sign(40) FROM src LIMIT 1;
  1sinsin(x) - returns the sine of x (x is in radians)
Example:
   > SELECT sin(0) FROM src LIMIT 1;
  0sizesize(a) - Returns the size of asort_arraysort_array(array(obj1, obj2,...)) - Sorts the input array in ascending order according to the natural ordering of the array elements.
Example:
  > SELECT sort_array(array('b', 'd', 'c', 'a')) FROM src LIMIT 1;
  'a', 'b', 'c', 'd'sort_array_bysort_array_by(array(obj1, obj2,...),'f1','f2',...,['ASC','DESC']) - Sorts the input tuple array in user specified order(ASC,DESC) by desired field[s] name If sorting order is not mentioned by user then dafault sorting order is ascending
Example:
  > SELECT sort_array_by(array(struct('g',100),struct('b',200)),'col1','ASC') FROM src LIMIT 1;
 array(struct('b',200),struct('g',100)) soundexsoundex(string) - Returns soundex code of the string.
The soundex code consist of the first letter of the name followed by three digits.
Example:
 > SELECT soundex('Miller');
 M460spacespace(n) - returns n spaces
Example:
   > SELECT space(2) FROM src LIMIT 1;
  '  'splitsplit(str, regex) - Splits str around occurances that match regex
Example:
  > SELECT split('oneAtwoBthreeC', '[ABC]') FROM src LIMIT 1;
  ["one", "two", "three"]sq_count_checksq_count_check(x) - Internal check on scalar subquery expression to make sure atmost one row is returned
For internal use onlysqrtsqrt(x) - returns the square root of x
Example:
   > SELECT sqrt(4) FROM src LIMIT 1;
  2stackstack(n, cols...) - turns k columns into n rows of size k/n eachstdstd(x) - Returns the standard deviation of a set of numbers
Synonyms: stddev, stddev_popstddevstddev(x) - Returns the standard deviation of a set of numbers
Synonyms: std, stddev_popstddev_popstddev_pop(x) - Returns the standard deviation of a set of numbers
Synonyms: std, stddevstddev_sampstddev_samp(x) - Returns the sample standard deviation of a set of numbersstr_to_mapstr_to_map(text, delimiter1, delimiter2) - Creates a map by parsing text
Split text into key-value pairs using two delimiters. The first delimiter separates pairs, and the second delimiter sperates key and value. If only one parameter is given, default delimiters are used: ',' as delimiter1 and ':' as delimiter2.structstruct(col1, col2, col3, ...) - Creates a struct with the given field valuessubstrsubstr(str, pos[, len]) - returns the substring of str that starts at pos and is of length len orsubstr(bin, pos[, len]) - returns the slice of byte array that starts at pos and is of length len
Synonyms: substring
pos is a 1-based index. If pos<0 the starting position is determined by counting backwards from the end of str.
Example:
   > SELECT substr('Facebook', 5) FROM src LIMIT 1;
  'book'
  > SELECT substr('Facebook', -5) FROM src LIMIT 1;
  'ebook'
  > SELECT substr('Facebook', 5, 1) FROM src LIMIT 1;
  'b'substringsubstring(str, pos[, len]) - returns the substring of str that starts at pos and is of length len orsubstring(bin, pos[, len]) - returns the slice of byte array that starts at pos and is of length len
Synonyms: substr
pos is a 1-based index. If pos<0 the starting position is determined by counting backwards from the end of str.
Example:
   > SELECT substring('Facebook', 5) FROM src LIMIT 1;
  'book'
  > SELECT substring('Facebook', -5) FROM src LIMIT 1;
  'ebook'
  > SELECT substring('Facebook', 5, 1) FROM src LIMIT 1;
  'b'substring_indexsubstring_index(str, delim, count) - Returns the substring from string str 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:
 > SELECT substring_index('www.apache.org', '.', 2);
 'www.apache'sumsum(x) - Returns the sum of a set of numberstantan(x) - returns the tangent of x (x is in radians)
Example:
   > SELECT tan(0) FROM src LIMIT 1;
  1to_dateto_date(expr) - Extracts the date part of the date or datetime expression expr
Example:
   > SELECT to_date('2009-07-30 04:17:52') FROM src LIMIT 1;
  '2009-07-30'to_unix_timestampto_unix_timestamp(date[, pattern]) - Returns the UNIX timestamp
Converts the specified time to number of seconds since 1970-01-01.to_utc_timestampto_utc_timestamp(timestamp, string timezone) - Assumes given timestamp is in given timezone and converts to UTC (as of Hive 0.8.0)translatetranslate(input, from, to) - translates the input string by replacing the characters present in the from string with the corresponding characters in the to string
translate(string input, string from, string to) is an equivalent function to translate in PostGreSQL. It works on a character by character basis on the input string (first parameter). A character in the input is checked for presence in the from string (second parameter). If a match happens, the character from to string (third parameter) which appears at the same index as the character in from string is obtained. This character is emitted in the output string  instead of the original character from the input string. If the to string is shorter than the from string, there may not be a character present at the same index in the to string. In such a case, nothing is emitted for the original character and it's deleted from the output string.
For example,

translate('abcdef', 'adc', '19') returns '1b9ef' replacing 'a' with '1', 'd' with '9' and removing 'c' from the input string

translate('a b c d', ' ', '') return 'abcd' removing all spaces from the input string

If the same character is present multiple times in the input string, the first occurence of the character is the one that's considered for matching. However, it is not recommended to have the same character more than once in the from string since it's not required and adds to confusion.

For example,

translate('abcdef', 'ada', '192') returns '1bc9ef' replaces 'a' with '1' and 'd' with '9' ignoring the second occurence of 'a' in the from string mapping it to '2'trimtrim(str) - Removes the leading and trailing space characters from str
Example:
  > SELECT trim('   facebook  ') FROM src LIMIT 1;
  'facebook'trunctrunc(date, fmt) / trunc(N,D) - Returns If input is date returns date with the time portion of the day truncated to the unit specified by the format model fmt. If you omit fmt, then date is truncated to the nearest day. It currently only supports 'MONTH'/'MON'/'MM', 'QUARTER'/'Q' and 'YEAR'/'YYYY'/'YY' as format.If input is a number group returns N truncated to D decimal places. If D is omitted, then N is truncated to 0 places.D can be negative to truncate (make zero) D digits left of the decimal point.
date is a string in the format 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. The time part of date is ignored.
Example:
  > SELECT trunc('2009-02-12', 'MM');
OK
 '2009-02-01'
 > SELECT trunc('2017-03-15', 'Q');
OK
 '2017-01-01'
 > SELECT trunc('2015-10-27', 'YEAR');
OK
 '2015-01-01' > SELECT trunc(1234567891.1234567891,4);
OK
 1234567891.1234
 > SELECT trunc(1234567891.1234567891,-4);
OK
 1234560000 > SELECT trunc(1234567891.1234567891,0);
OK
 1234567891
 > SELECT trunc(1234567891.1234567891);
OK
 1234567891ucaseucase(str) - Returns str with all characters changed to uppercase
Synonyms: upper
Example:
  > SELECT ucase('Facebook') FROM src LIMIT 1;
  'FACEBOOK'unbase64unbase64(str) - Convert the argument from a base 64 string to binaryunhexunhex(str) - Converts hexadecimal argument to binary
Performs the inverse operation of HEX(str). That is, it interprets
each pair of hexadecimal digits in the argument as a number and
converts it to the byte representation of the number. The
resulting characters are returned as a binary string.

Example:
> SELECT DECODE(UNHEX('4D7953514C'), 'UTF-8') from src limit 1;
'MySQL'

The characters in the argument string must be legal hexadecimal
digits: '0' .. '9', 'A' .. 'F', 'a' .. 'f'. If UNHEX() encounters
any nonhexadecimal digits in the argument, it returns NULL. Also,
if there are an odd number of characters a leading 0 is appended.unix_timestampunix_timestamp(date[, pattern]) - Converts the time to a number
Converts the specified time to number of seconds since 1970-01-01. The unix_timestamp(void) overload is deprecated, use current_timestamp.upperupper(str) - Returns str with all characters changed to uppercase
Synonyms: ucase
Example:
  > SELECT upper('Facebook') FROM src LIMIT 1;
  'FACEBOOK'uuiduuid() - Returns a universally unique identifier (UUID) string.
The value is returned as a canonical UUID 36-character string.
Example:
  > SELECT uuid();
  '0baf1f52-53df-487f-8292-99a03716b688'
  > SELECT uuid();
  '36718a53-84f5-45d6-8796-4f79983ad49d'var_popvar_pop(x) - Returns the variance of a set of numbers
Synonyms: variancevar_sampvar_samp(x) - Returns the sample variance of a set of numbersvariancevariance(x) - Returns the variance of a set of numbers
Synonyms: var_popversionversion() - Returns the Hive build version string - includes base version and revision.weekofyearweekofyear(date) - Returns the week of the year of the given date. A week is considered to start on a Monday and week 1 is the first week with >3 days.
Examples:
  > SELECT weekofyear('2008-02-20') FROM src LIMIT 1;
  8
  > SELECT weekofyear('1980-12-31 12:59:59') FROM src LIMIT 1;
  1whenCASE WHEN a THEN b [WHEN c THEN d]* [ELSE e] END - When a = true, returns b; when c = true, return d; else return e
Example:
 SELECT
 CASE
   WHEN deptno=1 THEN Engineering
   WHEN deptno=2 THEN Finance
   ELSE admin
 END,
 CASE
   WHEN zone=7 THEN Americas
   ELSE Asia-Pac
 END
 FROM emp_detailswindowingtablefunctionxpathxpath(xml, xpath) - Returns a string array of values within xml nodes that match the xpath expression
Example:
  > SELECT xpath('<a><b>b1</b><b>b2</b><b>b3</b><c>c1</c><c>c2</c></a>', 'a/text()') FROM src LIMIT 1
  []
  > SELECT xpath('<a><b>b1</b><b>b2</b><b>b3</b><c>c1</c><c>c2</c></a>', 'a/b/text()') FROM src LIMIT 1
  ["b1","b2","b3"]
  > SELECT xpath('<a><b>b1</b><b>b2</b><b>b3</b><c>c1</c><c>c2</c></a>', 'a/c/text()') FROM src LIMIT 1
  ["c1","c2"]xpath_booleanxpath_boolean(xml, xpath) - Evaluates a boolean xpath expression
Example:
  > SELECT xpath_boolean('<a><b>1</b></a>','a/b') FROM src LIMIT 1;
  true
  > SELECT xpath_boolean('<a><b>1</b></a>','a/b = 2') FROM src LIMIT 1;
  falsexpath_doublexpath_double(xml, xpath) - Returns a double value that matches the xpath expression
Synonyms: xpath_number
Example:
  > SELECT xpath_double('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3.0xpath_floatxpath_float(xml, xpath) - Returns a float value that matches the xpath expression
Example:
  > SELECT xpath_float('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3.0xpath_intxpath_int(xml, xpath) - Returns an integer value that matches the xpath expression
Example:
  > SELECT xpath_int('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3xpath_longxpath_long(xml, xpath) - Returns a long value that matches the xpath expression
Example:
  > SELECT xpath_long('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3xpath_numberxpath_number(xml, xpath) - Returns a double value that matches the xpath expression
Synonyms: xpath_double
Example:
  > SELECT xpath_number('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3.0xpath_shortxpath_short(xml, xpath) - Returns a short value that matches the xpath expression
Example:
  > SELECT xpath_short('<a><b>1</b><b>2</b></a>','sum(a/b)') FROM src LIMIT 1;
  3xpath_stringxpath_string(xml, xpath) - Returns the text contents of the first xml node that matches the xpath expression
Example:
  > SELECT xpath_string('<a><b>b</b><c>cc</c></a>','a/c') FROM src LIMIT 1;
  'cc'
  > SELECT xpath_string('<a><b>b1</b><b>b2</b></a>','a/b') FROM src LIMIT 1;
  'b1'
  > SELECT xpath_string('<a><b>b1</b><b>b2</b></a>','a/b[2]') FROM src LIMIT 1;
  'b2'
  > SELECT xpath_string('<a><b>b1</b><b>b2</b></a>','a') FROM src LIMIT 1;
  'b1b2'yearyear(param) - Returns the year component of the date/timestamp/interval
param can be one of:
1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.
2. A date value
3. A timestamp value
4. A year-month interval valueExample:
   > SELECT year('2009-07-30') FROM src LIMIT 1;
  2009
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