Hive常用函数有哪些

round(double d)

round(double d,int n)

floor(double d)

ceil(double d)

ceiling(double d)

rand() 

rand(int seed)

exp(double d)

ln(double d)

log10(double d)

log2(double d)

log(double base,double d)

pow(double d,double p)

power(double d,double p)

sqrt(double d)

hex(bigint i)

hex(string str)

abs(double d)

PI()

size(Map<K.V>)

map_keys(Map<K.V>)

map_values(Map<K.V>)

array_contains(Array<T>, value)

sort_array(Array<T>)

cast(expr as <type>)

date_add

date_sub

next_day

last_day

from_unixtime(bigint unixtime, string format)

to_date(string timestamp)

year(string date)

month(string date)

hour(string date)

weekofyear(string date)

datediff(string enddate, string startdate)

add_months(string start_date, int num_months)

date_format(date/timestamp/string ts, string fmt)

if(boolean testCondition, T valueTrue, T valueFalseOrNull)

nvl(T value, T default_value)

COALESCE(T v1, T v2, ...)

CASE a WHEN b THEN c [WHEN d THEN e]* [ELSE f] END

isnull( a )

isnotnull ( a )

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

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

length(string A)

lower(string A) lcase(string A)

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

regexp_replace(string INITIAL_STRING, string PATTERN, string REPLACEMENT)

reverse(string A)

split(string str, string pat)

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

count(*)

count(expr)

count(distinct expr[,expr_.])

sum(col)

sum(distinct col)

avg(col)

avg(distinct col)

min(col)

max(col)

explode(ARRAY array)

explode(MAP map)

explode(ARRAY<TYPE> a)

json_tuple(STRING jsonStr,p1p2,…,pn)-

parse_url_tuple(url,partname1,partname2,…,partnameN)