Spark--sql--所有函数举例(spark-2.x版本)

! expr - Logical not.
%
expr1 % expr2 - Returns the remainder afterexpr1/expr2.

Examples:

> SELECT  % 1.8;
 0.2
> SELECT MOD(, 1.8);
 0.2
&
expr1 & expr2 - Returns the result of bitwise AND ofexpr1andexpr2.

Examples:

> SELECT  & ;

*
expr1 * expr2 - Returnsexpr1*expr2.

Examples:

> SELECT  * ;

+
expr1 + expr2 - Returnsexpr1+expr2.

Examples:

> SELECT  + ;

-
expr1 - expr2 - Returnsexpr1-expr2.

Examples:

> SELECT  - ;

/
expr1 / expr2 - Returnsexpr1/expr2. It always performs floating point division.

Examples:

> SELECT  / ;
 1.5
> SELECT 2L / 2L;
 1.0
<
expr1 < expr2 - Returns true ifexpr1is less thanexpr2.

<=
expr1 <= expr2 - Returns true ifexpr1is less than or equal toexpr2.

<=>
expr1 <=> expr2 - Returns same result as the EQUAL(=) operator for non-null operands, but returns true if both are null, false if one of the them is null.

=
expr1 = expr2 - Returns true ifexpr1equalsexpr2, or false otherwise.

==
expr1 == expr2 - Returns true ifexpr1equalsexpr2, or false otherwise.

>
expr1 > expr2 - Returns true ifexpr1is greater thanexpr2.

>=
expr1 >= expr2 - Returns true ifexpr1is greater than or equal toexpr2.

^
expr1 ^ expr2 - Returns the result of bitwise exclusive OR ofexpr1andexpr2.

Examples:

> SELECT  ^ ;

abs
abs(expr) - Returns the absolute value of the numeric value.

Examples:

> SELECT abs(-);

acos
acos(expr) - Returns the inverse cosine (a.k.a. arccosine) ofexprif -<=expr<= or NaN otherwise.

Examples:

> SELECT acos();
 0.0
> SELECT acos();
 NaN
add_months
add_months(start_date, num_months) - Returns the date that isnum_monthsafterstart_date.

Examples:

> SELECT add_months('2016-08-31', );
 --
and
expr1 and expr2 - Logical AND.

approx_count_distinct
approx_count_distinct(expr[, relativeSD]) - Returns the estimated cardinality by HyperLogLog++.relativeSDdefines the maximum estimation error allowed.

approx_percentile
approx_percentile(col, percentage [, accuracy]) - Returns the approximate percentile value of numeric columncolat the given percentage. The value of percentage must be between 0.0 and 1.0. Theaccuracyparameter (default: ) is a positive numeric literal which controls approximation accuracy at the cost of memory. Higher value ofaccuracyyields better accuracy,1.0/accuracyis the relative error of the approximation. Whenpercentageis an array, each value of the percentage array must be between 0.0 and 1.0. In this case, returns the approximate percentile array of columncolat the given percentage array.

Examples:

> SELECT approx_percentile(10.0, array(0.5, 0.4, 0.1), );
 [10.0,10.0,10.0]
> SELECT approx_percentile(10.0, 0.5, );
 10.0
array
array(expr, ...) - Returns an array with the given elements.

Examples:

> SELECT array(, , );
 [,,]
array_contains
array_contains(array, value) - Returns true if the array contains the value.

Examples:

> SELECT array_contains(array(, , ), );
 true
ascii
ascii(str) - Returns the numeric value of the first character ofstr.

Examples:

> SELECT ascii('');

> SELECT ascii();

asin
asin(expr) - Returns the inverse sine (a.k.a. arcsine) the arc sin ofexprif -<=expr<= or NaN otherwise.

Examples:

> SELECT asin();
 0.0
> SELECT asin();
 NaN
assert_true
assert_true(expr) - Throws an exception ifexpris not true.

Examples:

> SELECT assert_true( < );
 NULL
atan
atan(expr) - Returns the inverse tangent (a.k.a. arctangent).

Examples:

> SELECT atan();
 0.0
atan2
atan2(expr1, expr2) - Returns the angle in radians between the positive x-axis of a plane and the point given by the coordinates (expr1,expr2).

Examples:

> SELECT atan2(, );
 0.0
avg
avg(expr) - Returns the mean calculated from values of a group.

base64
base64(bin) - Converts the argument from a binarybinto a base  string.

Examples:

> SELECT base64('Spark SQL');
 U3BhcmsgU1FM
bigint
bigint(expr) - Casts the valueexprto the target data typebigint.

bin
bin(expr) - Returns the string representation of the long valueexprrepresented in binary.

Examples:

> SELECT bin();

> SELECT bin(-);

> SELECT bin(13.3);

binary
binary(expr) - Casts the valueexprto the target data typebinary.

bit_length
bit_length(expr) - Returns the bit length ofexpror number of bits in binary data.

Examples:

> SELECT bit_length('Spark SQL');

boolean
boolean(expr) - Casts the valueexprto the target data typeboolean.

bround
bround(expr, d) - Returnsexprrounded toddecimal places using HALF_EVEN rounding mode.

Examples:

> SELECT bround(2.5, );
 2.0
cast
cast(expr AS type) - Casts the valueexprto the target data typetype.

Examples:

> SELECT cast('' as int);

cbrt
cbrt(expr) - Returns the cube root ofexpr.

Examples:

> SELECT cbrt(27.0);
 3.0
ceil
ceil(expr) - Returns the smallest integer not smaller thanexpr.

Examples:

> SELECT ceil(-0.1);

> SELECT ceil();

ceiling
ceiling(expr) - Returns the smallest integer not smaller thanexpr.

Examples:

> SELECT ceiling(-0.1);

> SELECT ceiling();

char
char(expr) - Returns the ASCII character having the binary equivalent toexpr. If n is larger than  the result is equivalent to chr(n % )

Examples:

> SELECT char();
 A
char_length
char_length(expr) - Returns the character length ofexpror number of bytes in binary data.

Examples:

> SELECT char_length('Spark SQL');

> SELECT CHAR_LENGTH('Spark SQL');

> SELECT CHARACTER_LENGTH('Spark SQL');

character_length
character_length(expr) - Returns the character length ofexpror number of bytes in binary data.

Examples:

> SELECT character_length('Spark SQL');

> SELECT CHAR_LENGTH('Spark SQL');

> SELECT CHARACTER_LENGTH('Spark SQL');

chr
chr(expr) - Returns the ASCII character having the binary equivalent toexpr. If n is larger than  the result is equivalent to chr(n % )

Examples:

> SELECT chr();
 A
coalesce
coalesce(expr1, expr2, ...) - Returns the first non-null argument if exists. Otherwise, null.

Examples:

> SELECT coalesce(NULL, , NULL);

collect_list
collect_list(expr) - Collects and returns a list of non-unique elements.

collect_set
collect_set(expr) - Collects and returns a set of unique elements.

concat
concat(str1, str2, ..., strN) - Returns the concatenation of str1, str2, ..., strN.

Examples:

> SELECT concat('Spark', 'SQL');
 SparkSQL
concat_ws
concat_ws(sep, [str | array(str)]+) - Returns the concatenation of the strings separated bysep.

Examples:

> SELECT concat_ws(' ', 'Spark', 'SQL');
  Spark SQL
conv
conv(num, from_base, to_base) - Convertnumfromfrom_basetoto_base.

Examples:

> SELECT conv('', , );

> SELECT conv(-, , -);
 -
corr
corr(expr1, expr2) - Returns Pearson coefficient of correlation between a set of number pairs.

cos
cos(expr) - Returns the cosine ofexpr.

Examples:

> SELECT cos();
 1.0
cosh
cosh(expr) - Returns the hyperbolic cosine ofexpr.

Examples:

> SELECT cosh();
 1.0
cot
cot(expr) - Returns the cotangent ofexpr.

Examples:

> SELECT cot();
 0.6420926159343306
count
count(*) - Returns the total number of retrieved rows, including rows containing null.

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.

count_min_sketch
count_min_sketch(col, eps, confidence, seed) - Returns a count-min sketch of a column with the given esp, confidence and seed. The result is an array of bytes, which can be deserialized to aCountMinSketchbefore usage. Count-min sketch is a probabilistic data structure used for cardinality estimation using sub-linear space.

covar_pop
covar_pop(expr1, expr2) - Returns the population covariance of a set of number pairs.

covar_samp
covar_samp(expr1, expr2) - Returns the sample covariance of a set of number pairs.

crc32
crc32(expr) - Returns a cyclic redundancy check value of theexpras a bigint.

Examples:

> SELECT crc32('Spark');

cube
cume_dist
cume_dist() - Computes the position of a value relative to all values in the partition.

current_database
current_database() - Returns the current database.

Examples:

> SELECT current_database();
 default
current_date
current_date() - Returns the current date at the start of query evaluation.

current_timestamp
current_timestamp() - Returns the current timestamp at the start of query evaluation.

date
date(expr) - Casts the valueexprto the target data typedate.

date_add
date_add(start_date, num_days) - Returns the date that isnum_daysafterstart_date.

Examples:

> SELECT date_add('2016-07-30', );
 --
date_format
date_format(timestamp, fmt) - Convertstimestampto a value of string in the format specified by the date formatfmt.

Examples:

> SELECT date_format('2016-04-08', 'y');

date_sub
date_sub(start_date, num_days) - Returns the date that isnum_daysbeforestart_date.

Examples:

> SELECT date_sub('2016-07-30', );
 --
datediff
datediff(endDate, startDate) - Returns the number of days fromstartDatetoendDate.

Examples:

> SELECT datediff('2009-07-31', '2009-07-30');

> SELECT datediff('2009-07-30', '2009-07-31');
 -
day
day(date) - Returns the day of month of the date/timestamp.

Examples:

> SELECT day('2009-07-30');

dayofmonth
dayofmonth(date) - Returns the day of month of the date/timestamp.

Examples:

> SELECT dayofmonth('2009-07-30');

dayofweek
dayofweek(date) - Returns the day of the week for date/timestamp ( = Sunday,  = Monday, ...,  = Saturday).

Examples:

> SELECT dayofweek('2009-07-30');

dayofyear
dayofyear(date) - Returns the day of year of the date/timestamp.

Examples:

> SELECT dayofyear('2016-04-09');

decimal
decimal(expr) - Casts the valueexprto the target data typedecimal.

decode
decode(bin, charset) - Decodes the first argument using the second argument character set.

Examples:

> SELECT decode(encode('abc', 'utf-8'), 'utf-8');
 abc
degrees
degrees(expr) - Converts radians to degrees.

Examples:

> SELECT degrees(3.141592653589793);
 180.0
dense_rank
dense_rank() - Computes the rank of a value in a group of values. The result is one plus the previously assigned rank value. Unlike the function rank, dense_rank will not produce gaps in the ranking sequence.

double
double(expr) - Casts the valueexprto the target data typedouble.

e
e() - Returns Euler's number, e.

Examples:

> SELECT e();
 2.718281828459045
elt
elt(n, str1, str2, ...) - Returns then-th string, e.g., returnsstr2whennis .

Examples:

> SELECT elt(, 'scala', 'java');
 scala
encode
encode(str, charset) - Encodes the first argument using the second argument character set.

Examples:

> SELECT encode('abc', 'utf-8');
 abc
exp
exp(expr) - Returns e to the power ofexpr.

Examples:

> SELECT exp();
 1.0
explode
explode(expr) - Separates the elements of arrayexprinto multiple rows, or the elements of mapexprinto multiple rows and columns.

Examples:

> SELECT explode(array(, ));

explode_outer
explode_outer(expr) - Separates the elements of arrayexprinto multiple rows, or the elements of mapexprinto multiple rows and columns.

Examples:

> SELECT explode_outer(array(, ));

expm1
expm1(expr) - Returns exp(expr) - .

Examples:

> SELECT expm1();
 0.0
factorial
factorial(expr) - Returns the factorial ofexpr.expris [..]. Otherwise, null.

Examples:

> SELECT factorial();

find_in_set
find_in_set(str, str_array) - Returns the index (-based) of the given string (str) in the comma-delimited list (str_array). Returns , if the string was not found or if the given string (str) contains a comma.

Examples:

> SELECT find_in_set('ab','abc,b,ab,c,def');

first
first(expr[, isIgnoreNull]) - Returns the first value ofexprfor a group of rows. IfisIgnoreNullis true, returns only non-null values.

first_value
first_value(expr[, isIgnoreNull]) - Returns the first value ofexprfor a group of rows. IfisIgnoreNullis true, returns only non-null values.

float
float(expr) - Casts the valueexprto the target data typefloat.

floor
floor(expr) - Returns the largest integer not greater thanexpr.

Examples:

> SELECT floor(-0.1);
 -
> SELECT floor();

format_number
format_number(expr1, expr2) - Formats the numberexpr1like '#,###,###.##', rounded toexpr2decimal places. Ifexpr2is , the result has no decimal point or fractional part. This is supposed to function like MySQL's FORMAT.

Examples:

> SELECT format_number(12332.123456, );
 ,332.1235
format_string
format_string(strfmt, obj, ...) - Returns a formatted string from printf-style format strings.

Examples:

> SELECT format_string("Hello World %d %s", , "days");
 Hello World  days
from_json
from_json(jsonStr, schema[, options]) - Returns a struct value with the givenjsonStrandschema.

Examples:

> SELECT from_json('{"a":1, "b":0.8}', 'a INT, b DOUBLE');
 {"a":, "b":0.8}
> SELECT from_json('{"time":"26/08/2015"}', 'time Timestamp', map('timestampFormat', 'dd/MM/yyyy'));
 {"time":"2015-08-26 00:00:00.0"}
Since:2.2.

from_unixtime
from_unixtime(unix_time, format) - Returnsunix_timein the specifiedformat.

Examples:

> SELECT from_unixtime(, 'yyyy-MM-dd HH:mm:ss');
 -- ::
from_utc_timestamp
from_utc_timestamp(timestamp, timezone) - Given a timestamp, which corresponds to a certain time of day in UTC, returns another timestamp that corresponds to the same time of day in the given timezone.

Examples:

> SELECT from_utc_timestamp('2016-08-31', 'Asia/Seoul');
 -- ::
get_json_object
get_json_object(json_txt, path) - Extracts a json object frompath.

Examples:

> SELECT get_json_object('{"a":"b"}', '$.a');
 b
greatest
greatest(expr, ...) - Returns the greatest value of all parameters, skipping null values.

Examples:

> SELECT greatest(, , , , );

grouping
grouping_id
hash
hash(expr1, expr2, ...) - Returns a hash value of the arguments.

Examples:

> SELECT hash('Spark', array(), );
 -
hex
hex(expr) - Convertsexprto hexadecimal.

Examples:

> SELECT hex();

> SELECT hex('Spark SQL');
 537061726B2053514C
hour
hour(timestamp) - Returns the hour component of the string/timestamp.

Examples:

> SELECT hour('2009-07-30 12:58:59');

hypot
hypot(expr1, expr2) - Returns sqrt(expr12 +expr22).

Examples:

> SELECT hypot(, );
 5.0
if
if(expr1, expr2, expr3) - Ifexpr1evaluates to true, then returnsexpr2; otherwise returnsexpr3.

Examples:

> SELECT if( < , 'a', 'b');
 a
ifnull
ifnull(expr1, expr2) - Returnsexpr2ifexpr1is null, orexpr1otherwise.

Examples:

> SELECT ifnull(NULL, array(''));
 [""]
in
expr1 in(expr2, expr3, ...) - Returns true ifexprequals to any valN.

initcap
initcap(str) - Returnsstrwith the first letter of each word in uppercase. All other letters are in lowercase. Words are delimited by white space.

Examples:

> SELECT initcap('sPark sql');
 Spark Sql
inline
inline(expr) - Explodes an array of structs into a table.

Examples:

> SELECT inline(array(struct(, 'a'), struct(, 'b')));
   a
   b
inline_outer
inline_outer(expr) - Explodes an array of structs into a table.

Examples:

> SELECT inline_outer(array(struct(, 'a'), struct(, 'b')));
   a
   b
input_file_block_length
input_file_block_length() - Returns the length of the block being read, or - if not available.

input_file_block_start
input_file_block_start() - Returns the start offset of the block being read, or - if not available.

input_file_name
input_file_name() - Returns the name of the file being read, or empty string if not available.

instr
instr(str, substr) - Returns the (-based) index of the first occurrence ofsubstrinstr.

Examples:

> SELECT instr('SparkSQL', 'SQL');

int
int(expr) - Casts the valueexprto the target data typeint.

isnan
isnan(expr) - Returns true ifexpris NaN, or false otherwise.

Examples:

> SELECT isnan(cast('NaN' as double));
 true
isnotnull
isnotnull(expr) - Returns true ifexpris not null, or false otherwise.

Examples:

> SELECT isnotnull();
 true
isnull
isnull(expr) - Returns true ifexpris null, or false otherwise.

Examples:

> SELECT isnull();
 false
java_method
java_method(class, method[, arg1[, arg2 ..]]) - Calls a method with reflection.

Examples:

> SELECT java_method('java.util.UUID', 'randomUUID');
 c33fb387--4bfa-81d2-6e0e3e930df2
> SELECT java_method('java.util.UUID', 'fromString', 'a5cf6c42-0c85-418f-af6c-3e4e5b1328f2');
 a5cf6c42-0c85-418f-af6c-3e4e5b1328f2
json_tuple
json_tuple(jsonStr, p1, p2, ..., pn) - Returns a tuple like the function get_json_object, but it takes multiple names. All the input parameters and output column types are string.

Examples:

> SELECT json_tuple('{"a":1, "b":2}', 'a', 'b');

kurtosis
kurtosis(expr) - Returns the kurtosis value calculated from values of a group.

lag
lag(input[, offset[, default]]) - Returns the value ofinputat theoffsetth row before the current row in the window. The default value ofoffsetis  and the default value ofdefaultis null. If the value ofinputat theoffsetth row is null, null is returned. If there is no such offset row (e.g., when the offset is , the first row of the window does not have any previous row),defaultis returned.

last
last(expr[, isIgnoreNull]) - Returns the last value ofexprfor a group of rows. IfisIgnoreNullis true, returns only non-null values.

last_day
last_day(date) - Returns the last day of the month which the date belongs to.

Examples:

> SELECT last_day('2009-01-12');
 --
last_value
last_value(expr[, isIgnoreNull]) - Returns the last value ofexprfor a group of rows. IfisIgnoreNullis true, returns only non-null values.

lcase
lcase(str) - Returnsstrwith all characters changed to lowercase.

Examples:

> SELECT lcase('SparkSql');
 sparksql
lead
lead(input[, offset[, default]]) - Returns the value ofinputat theoffsetth row after the current row in the window. The default value ofoffsetis  and the default value ofdefaultis null. If the value ofinputat theoffsetth row is null, null is returned. If there is no such an offset row (e.g., when the offset is , the last row of the window does not have any subsequent row),defaultis returned.

least
least(expr, ...) - Returns the least value of all parameters, skipping null values.

Examples:

> SELECT least(, , , , );

left
left(str, len) - Returns the leftmostlen(lencan be string type) characters from the stringstr,iflenis less or equal than  the result is an empty string.

Examples:

> SELECT left('Spark SQL', );
 Spa
length
length(expr) - Returns the character length ofexpror number of bytes in binary data.

Examples:

> SELECT length('Spark SQL');

> SELECT CHAR_LENGTH('Spark SQL');

> SELECT CHARACTER_LENGTH('Spark SQL');

levenshtein
levenshtein(str1, str2) - Returns the Levenshtein distance between the two given strings.

Examples:

> SELECT levenshtein('kitten', 'sitting');

like
str like pattern - Returns true if str matches pattern, null if any arguments are null, false otherwise.

Arguments:

str - a string expression

pattern - a string expression. The pattern is a string which is matched literally, with exception to the following special symbols:

_ matches any one character in the input (similar to . in posix regular expressions)

% matches zero or more characters in the input (similar to .* in posix regular expressions)

The escape character is '\'. If an escape character precedes a special symbol or another escape character, the following character is matched literally. It is invalid to escape any other character.

Since Spark 2.0, string literals are unescaped in our SQL parser. For example, in order to match "\abc", the pattern should be "\abc".

When SQL config 'spark.sql.parser.escapedStringLiterals' is enabled, it fallbacks to Spark 1.6 behavior regarding string literal parsing. For example, if the config is enabled, the pattern to match "\abc" should be "\abc".

Examples:

> SELECT '%SystemDrive%\Users\John' like '\%SystemDrive\%\\Users%'
true
Note:

Use RLIKE to match with standard regular expressions.

ln
ln(expr) - Returns the natural logarithm (base e) ofexpr.

Examples:

> SELECT ln();
 0.0
locate
locate(substr, str[, pos]) - Returns the position of the first occurrence ofsubstrinstrafter positionpos. The givenposand return value are -based.

Examples:

> SELECT locate('bar', 'foobarbar');

> SELECT locate('bar', 'foobarbar', );

> SELECT POSITION('bar' IN 'foobarbar');

log
log(base, expr) - Returns the logarithm ofexprwithbase.

Examples:

> SELECT log(, );
 2.0
log10
log10(expr) - Returns the logarithm ofexprwith base .

Examples:

> SELECT log10();
 1.0
log1p
log1p(expr) - Returns log( +expr).

Examples:

> SELECT log1p();
 0.0
log2
log2(expr) - Returns the logarithm ofexprwith base .

Examples:

> SELECT log2();
 1.0
lower
lower(str) - Returnsstrwith all characters changed to lowercase.

Examples:

> SELECT lower('SparkSql');
 sparksql
lpad
lpad(str, len, pad) - Returnsstr, left-padded withpadto a length oflen. Ifstris longer thanlen, the return value is shortened tolencharacters.

Examples:

> SELECT lpad('hi', , '');
 hi
> SELECT lpad('hi', , '');
 h
ltrim
ltrim(str) - Removes the leading and trailing space characters fromstr.

Examples:

> SELECT ltrim('    SparkSQL');
 SparkSQL
map
map(key0, value0, key1, value1, ...) - Creates a map with the given key/value pairs.

Examples:

> SELECT map(1.0, '', 3.0, '');
 {1.0:"",3.0:""}
map_keys
map_keys(map) - Returns an unordered array containing the keys of the map.

Examples:

> SELECT map_keys(map(, 'a', , 'b'));
 [,]
map_values
map_values(map) - Returns an unordered array containing the values of the map.

Examples:

> SELECT map_values(map(, 'a', , 'b'));
 ["a","b"]
max
max(expr) - Returns the maximum value ofexpr.

md5
md5(expr) - Returns an MD5 -bit checksum as a hex string ofexpr.

Examples:

> SELECT md5('Spark');
 8cde774d6f7333752ed72cacddb05126
mean
mean(expr) - Returns the mean calculated from values of a group.

min
min(expr) - Returns the minimum value ofexpr.

minute
minute(timestamp) - Returns the minute component of the string/timestamp.

Examples:

> SELECT minute('2009-07-30 12:58:59');

mod
expr1 mod expr2 - Returns the remainder afterexpr1/expr2.

Examples:

> SELECT  mod 1.8;
 0.2
> SELECT MOD(, 1.8);
 0.2
monotonically_increasing_id
monotonically_increasing_id() - Returns monotonically increasing -bit integers. The generated ID is guaranteed to be monotonically increasing and unique, but not consecutive. The current implementation puts the partition ID in the upper  bits, and the lower  bits represent the record number within each partition. The assumption is that the data frame has less than  billion partitions, and each partition has less than  billion records.

month
month(date) - Returns the month component of the date/timestamp.

Examples:

> SELECT month('2016-07-30');

months_between
months_between(timestamp1, timestamp2) - Returns number of months betweentimestamp1andtimestamp2.

Examples:

> SELECT months_between('1997-02-28 10:30:00', '1996-10-30');
 3.94959677
named_struct
named_struct(name1, val1, name2, val2, ...) - Creates a struct with the given field names and values.

Examples:

> SELECT named_struct("a", , "b", , "c", );
 {"a":,"b":,"c":}
nanvl
nanvl(expr1, expr2) - Returnsexpr1if it's not NaN, orexpr2otherwise.

Examples:

> SELECT nanvl(cast('NaN' as double), );
 123.0
negative
negative(expr) - Returns the negated value ofexpr.

Examples:

> SELECT negative();
 -
next_day
next_day(start_date, day_of_week) - Returns the first date which is later thanstart_dateand named as indicated.

Examples:

> SELECT next_day('2015-01-14', 'TU');
 --
not
not expr - Logical not.

now
now() - Returns the current timestamp at the start of query evaluation.

ntile
ntile(n) - Divides the rows for each window partition intonbuckets ranging from  to at mostn.

nullif
nullif(expr1, expr2) - Returns null ifexpr1equals toexpr2, orexpr1otherwise.

Examples:

> SELECT nullif(, );
 NULL
nvl
nvl(expr1, expr2) - Returnsexpr2ifexpr1is null, orexpr1otherwise.

Examples:

> SELECT nvl(NULL, array(''));
 [""]
nvl2
nvl2(expr1, expr2, expr3) - Returnsexpr2ifexpr1is not null, orexpr3otherwise.

Examples:

> SELECT nvl2(NULL, , );

octet_length
octet_length(expr) - Returns the byte length ofexpror number of bytes in binary data.

Examples:

> SELECT octet_length('Spark SQL');

or
expr1 or expr2 - Logical OR.

parse_url
parse_url(url, partToExtract[, key]) - Extracts a part from a URL.

Examples:

> SELECT parse_url('http://spark.apache.org/pathquery=1', 'HOST')
 spark.apache.org
> SELECT parse_url('http://spark.apache.org/pathquery=1', 'QUERY')
 query=
> SELECT parse_url('http://spark.apache.org/pathquery=1', 'QUERY', 'query')

percent_rank
percent_rank() - Computes the percentage ranking of a value in a group of values.

percentile
percentile(col, percentage [, frequency]) - Returns the exact percentile value of numeric columncolat the given percentage. The value of percentage must be between 0.0 and 1.0. The value of frequency should be positive integral

percentile(col, array(percentage1 [, percentage2]...) [, frequency]) - Returns the exact percentile value array of numeric columncolat the given percentage(s). Each value of the percentage array must be between 0.0 and 1.0. The value of frequency should be positive integral

percentile_approx
percentile_approx(col, percentage [, accuracy]) - Returns the approximate percentile value of numeric columncolat the given percentage. The value of percentage must be between 0.0 and 1.0. Theaccuracyparameter (default: ) is a positive numeric literal which controls approximation accuracy at the cost of memory. Higher value ofaccuracyyields better accuracy,1.0/accuracyis the relative error of the approximation. Whenpercentageis an array, each value of the percentage array must be between 0.0 and 1.0. In this case, returns the approximate percentile array of columncolat the given percentage array.

Examples:

> SELECT percentile_approx(10.0, array(0.5, 0.4, 0.1), );
 [10.0,10.0,10.0]
> SELECT percentile_approx(10.0, 0.5, );
 10.0
pi
pi() - Returns pi.

Examples:

> SELECT pi();
 3.141592653589793
pmod
pmod(expr1, expr2) - Returns the positive value ofexpr1modexpr2.

Examples:

> SELECT pmod(, );

> SELECT pmod(-, );

posexplode
posexplode(expr) - Separates the elements of arrayexprinto multiple rows with positions, or the elements of mapexprinto multiple rows and columns with positions.

Examples:

> SELECT posexplode(array(,));

posexplode_outer
posexplode_outer(expr) - Separates the elements of arrayexprinto multiple rows with positions, or the elements of mapexprinto multiple rows and columns with positions.

Examples:

> SELECT posexplode_outer(array(,));

position
position(substr, str[, pos]) - Returns the position of the first occurrence ofsubstrinstrafter positionpos. The givenposand return value are -based.

Examples:

> SELECT position('bar', 'foobarbar');

> SELECT position('bar', 'foobarbar', );

> SELECT POSITION('bar' IN 'foobarbar');

positive
positive(expr) - Returns the value ofexpr.

pow
pow(expr1, expr2) - Raisesexpr1to the power ofexpr2.

Examples:

> SELECT pow(, );
 8.0
power
power(expr1, expr2) - Raisesexpr1to the power ofexpr2.

Examples:

> SELECT power(, );
 8.0
printf
printf(strfmt, obj, ...) - Returns a formatted string from printf-style format strings.

Examples:

> SELECT printf("Hello World %d %s", , "days");
 Hello World  days
quarter
quarter(date) - Returns the quarter of the year for date, in the range  to .

Examples:

> SELECT quarter('2016-08-31');

radians
radians(expr) - Converts degrees to radians.

Examples:

> SELECT radians();
 3.141592653589793
rand
rand([seed]) - Returns a random value with independent and identically distributed (i.i.d.) uniformly distributed values in [, ).

Examples:

> SELECT rand();
 0.9629742951434543
> SELECT rand();
 0.8446490682263027
> SELECT rand(null);
 0.8446490682263027
randn
randn([seed]) - Returns a random value with independent and identically distributed (i.i.d.) values drawn from the standard normal distribution.

Examples:

> SELECT randn();
 -0.3254147983080288
> SELECT randn();
 1.1164209726833079
> SELECT randn(null);
 1.1164209726833079
rank
rank() - Computes the rank of a value in a group of values. The result is one plus the number of rows preceding or equal to the current row in the ordering of the partition. The values will produce gaps in the sequence.

reflect
reflect(class, method[, arg1[, arg2 ..]]) - Calls a method with reflection.

Examples:

> SELECT reflect('java.util.UUID', 'randomUUID');
 c33fb387--4bfa-81d2-6e0e3e930df2
> SELECT reflect('java.util.UUID', 'fromString', 'a5cf6c42-0c85-418f-af6c-3e4e5b1328f2');
 a5cf6c42-0c85-418f-af6c-3e4e5b1328f2
regexp_extract
regexp_extract(str, regexp[, idx]) - Extracts a group that matchesregexp.

Examples:

> SELECT regexp_extract('100-200', '(\d+)-(\d+)', );

regexp_replace
regexp_replace(str, regexp, rep) - Replaces all substrings ofstrthat matchregexpwithrep.

Examples:

> SELECT regexp_replace('100-200', '(\d+)', 'num');
 num-num
repeat
repeat(str, n) - Returns the string which repeats the given string value n times.

Examples:

> SELECT repeat('', );

replace
replace(str, search[, replace]) - Replaces all occurrences ofsearchwithreplace.

Arguments:

str - a string expression

search - a string expression. Ifsearchis not found instr,stris returned unchanged.

replace - a string expression. Ifreplaceis not specified or is an empty string, nothing replaces the string that is removed fromstr.

Examples:

> SELECT replace('ABCabc', 'abc', 'DEF');
 ABCDEF
reverse
reverse(str) - Returns the reversed given string.

Examples:

> SELECT reverse('Spark SQL');
 LQS krapS
right
right(str, len) - Returns the rightmostlen(lencan be string type) characters from the stringstr,iflenis less or equal than  the result is an empty string.

Examples:

> SELECT right('Spark SQL', );
 SQL
rint
rint(expr) - Returns the double value that is closest in value to the argument and is equal to a mathematical integer.

Examples:

> SELECT rint(12.3456);
 12.0
rlike
str rlike regexp - Returns true ifstrmatchesregexp, or false otherwise.

Arguments:

str - a string expression

regexp - a string expression. The pattern string should be a Java regular expression.

Since Spark 2.0, string literals (including regex patterns) are unescaped in our SQL parser. For example, to match "\abc", a regular expression forregexpcan be "^\abc$".

There is a SQL config 'spark.sql.parser.escapedStringLiterals' that can be used to fallback to the Spark 1.6 behavior regarding string literal parsing. For example, if the config is enabled, theregexpthat can match "\abc" is "^\abc$".

Examples:

When spark.sql.parser.escapedStringLiterals is disabled (default).
> SELECT '%SystemDrive%\Users\John' rlike '%SystemDrive%\\Users.*'
true

When spark.sql.parser.escapedStringLiterals is enabled.
> SELECT '%SystemDrive%\Users\John' rlike '%SystemDrive%\Users.*'
true
Note:

Use LIKE to match with simple string pattern.

rollup
round
round(expr, d) - Returnsexprrounded toddecimal places using HALF_UP rounding mode.

Examples:

> SELECT round(2.5, );
 3.0
row_number
row_number() - Assigns a unique, sequential number to each row, starting with one, according to the ordering of rows within the window partition.

rpad
rpad(str, len, pad) - Returnsstr, right-padded withpadto a length oflen. Ifstris longer thanlen, the return value is shortened tolencharacters.

Examples:

> SELECT rpad('hi', , '');
 hi
> SELECT rpad('hi', , '');
 h
rtrim
rtrim(str) - Removes the trailing space characters fromstr.

Examples:

> SELECT rtrim('    SparkSQL   ');
     SparkSQL
second
second(timestamp) - Returns the second component of the string/timestamp.

Examples:

> SELECT second('2009-07-30 12:58:59');

sentences
sentences(str[, lang, country]) - Splitsstrinto an array of array of words.

Examples:

> SELECT sentences('Hi there! Good morning.');
 [["Hi","there"],["Good","morning"]]
sha
sha(expr) - Returns a sha1 hash value as a hex string of theexpr.

Examples:

> SELECT sha('Spark');
 85f5955f4b27a9a4c2aab6ffe5d7189fc298b92c
sha1
sha1(expr) - Returns a sha1 hash value as a hex string of theexpr.

Examples:

> SELECT sha1('Spark');
 85f5955f4b27a9a4c2aab6ffe5d7189fc298b92c
sha2
sha2(expr, bitLength) - Returns a checksum of SHA- family as a hex string ofexpr. SHA-, SHA-, SHA-, and SHA- are supported. Bit length of  is equivalent to .

Examples:

> SELECT sha2('Spark', );
 529bc3b07127ecb7e53a4dcf1991d9152c24537d919178022b2c42657f79a26b
shiftleft
shiftleft(base, expr) - Bitwise left shift.

Examples:

> SELECT shiftleft(, );

shiftright
shiftright(base, expr) - Bitwise (signed) right shift.

Examples:

> SELECT shiftright(, );

shiftrightunsigned
shiftrightunsigned(base, expr) - Bitwise unsigned right shift.

Examples:

> SELECT shiftrightunsigned(, );

sign
sign(expr) - Returns -1.0, 0.0 or 1.0 asexpris negative,  or positive.

Examples:

> SELECT sign();
 1.0
signum
signum(expr) - Returns -1.0, 0.0 or 1.0 asexpris negative,  or positive.

Examples:

> SELECT signum();
 1.0
sin
sin(expr) - Returns the sine ofexpr.

Examples:

> SELECT sin();
 0.0
sinh
sinh(expr) - Returns the hyperbolic sine ofexpr.

Examples:

> SELECT sinh();
 0.0
size
size(expr) - Returns the size of an array or a map. Returns - if null.

Examples:

> SELECT size(array('b', 'd', 'c', 'a'));

skewness
skewness(expr) - Returns the skewness value calculated from values of a group.

smallint
smallint(expr) - Casts the valueexprto the target data typesmallint.

sort_array
sort_array(array[, ascendingOrder]) - Sorts the input array in ascending or descending order according to the natural ordering of the array elements.

Examples:

> SELECT sort_array(array('b', 'd', 'c', 'a'), true);
 ["a","b","c","d"]
soundex
soundex(str) - Returns Soundex code of the string.

Examples:

> SELECT soundex('Miller');
 M460
space
space(n) - Returns a string consisting ofnspaces.

Examples:

> SELECT concat(space(), '');

spark_partition_id
spark_partition_id() - Returns the current partition id.

split
split(str, regex) - Splitsstraround occurrences that matchregex.

Examples:

> SELECT split('oneAtwoBthreeC', '[ABC]');
 ["one","two","three",""]
sqrt
sqrt(expr) - Returns the square root ofexpr.

Examples:

> SELECT sqrt();
 2.0
stack
stack(n, expr1, ..., exprk) - Separatesexpr1, ...,exprkintonrows.

Examples:

> SELECT stack(, , , );

   NULL
std
std(expr) - Returns the sample standard deviation calculated from values of a group.

stddev
stddev(expr) - Returns the sample standard deviation calculated from values of a group.

stddev_pop
stddev_pop(expr) - Returns the population standard deviation calculated from values of a group.

stddev_samp
stddev_samp(expr) - Returns the sample standard deviation calculated from values of a group.

str_to_map
str_to_map(text[, pairDelim[, keyValueDelim]]) - Creates a map after splitting the text into key/value pairs using delimiters. Default delimiters are ',' forpairDelimand ':' forkeyValueDelim.

Examples:

> SELECT str_to_map('a:1,b:2,c:3', ',', ':');
 map("a":"","b":"","c":"")
> SELECT str_to_map('a');
 map("a":null)
string
string(expr) - Casts the valueexprto the target data typestring.

struct
struct(col1, col2, col3, ...) - Creates a struct with the given field values.

substr
substr(str, pos[, len]) - Returns the substring ofstrthat starts atposand is of lengthlen, or the slice of byte array that starts atposand is of lengthlen.

Examples:

> SELECT substr('Spark SQL', );
 k SQL
> SELECT substr('Spark SQL', -);
 SQL
> SELECT substr('Spark SQL', , );
 k
substring
substring(str, pos[, len]) - Returns the substring ofstrthat starts atposand is of lengthlen, or the slice of byte array that starts atposand is of lengthlen.

Examples:

> SELECT substring('Spark SQL', );
 k SQL
> SELECT substring('Spark SQL', -);
 SQL
> SELECT substring('Spark SQL', , );
 k
substring_index
substring_index(str, delim, count) - Returns the substring fromstrbeforecountoccurrences of the delimiterdelim. Ifcountis positive, everything to the left of the final delimiter (counting from the left) is returned. Ifcountis negative, everything to the right of the final delimiter (counting from the right) is returned. The function substring_index performs a case-sensitive match when searching fordelim.

Examples:

> SELECT substring_index('www.apache.org', '.', );
 www.apache
sum
sum(expr) - Returns the sum calculated from values of a group.

tan
tan(expr) - Returns the tangent ofexpr.

Examples:

> SELECT tan();
 0.0
tanh
tanh(expr) - Returns the hyperbolic tangent ofexpr.

Examples:

> SELECT tanh();
 0.0
timestamp
timestamp(expr) - Casts the valueexprto the target data typetimestamp.

tinyint
tinyint(expr) - Casts the valueexprto the target data typetinyint.

to_date
to_date(date_str[, fmt]) - Parses thedate_strexpression with thefmtexpression to a date. Returns null with invalid input. By default, it follows casting rules to a date if thefmtis omitted.

Examples:

> SELECT to_date('2009-07-30 04:17:52');
 --
> SELECT to_date('2016-12-31', 'yyyy-MM-dd');
 --
to_json
to_json(expr[, options]) - Returns a json string with a given struct value

Examples:

> SELECT to_json(named_struct('a', , 'b', ));
 {"a":,"b":}
> SELECT to_json(named_struct('time', to_timestamp('2015-08-26', 'yyyy-MM-dd')), map('timestampFormat', 'dd/MM/yyyy'));
 {"time":"26/08/2015"}
> SELECT to_json(array(named_struct('a', , 'b', ));
 [{"a":,"b":}]
Since:2.2.

to_timestamp
to_timestamp(timestamp[, fmt]) - Parses thetimestampexpression with thefmtexpression to a timestamp. Returns null with invalid input. By default, it follows casting rules to a timestamp if thefmtis omitted.

Examples:

> SELECT to_timestamp('2016-12-31 00:12:00');
 -- ::
> SELECT to_timestamp('2016-12-31', 'yyyy-MM-dd');
 -- ::
to_unix_timestamp
to_unix_timestamp(expr[, pattern]) - Returns the UNIX timestamp of the given time.

Examples:

> SELECT to_unix_timestamp('2016-04-08', 'yyyy-MM-dd');

to_utc_timestamp
to_utc_timestamp(timestamp, timezone) - Given a timestamp, which corresponds to a certain time of day in the given timezone, returns another timestamp that corresponds to the same time of day in UTC.

Examples:

> SELECT to_utc_timestamp('2016-08-31', 'Asia/Seoul');
 -- ::
translate
translate(input, from, to) - Translates theinputstring by replacing the characters present in thefromstring with the corresponding characters in thetostring.

Examples:

> SELECT translate('AaBbCc', 'abc', '');
 A1B2C3
trim
trim(str) - Removes the leading and trailing space characters fromstr.

Examples:

> SELECT trim('    SparkSQL   ');
 SparkSQL
trunc
trunc(date, fmt) - Returnsdatewith the time portion of the day truncated to the unit specified by the format modelfmt.

Examples:

> SELECT trunc('2009-02-12', 'MM');
 --
> SELECT trunc('2015-10-27', 'YEAR');
 --
ucase
ucase(str) - Returnsstrwith all characters changed to uppercase.

Examples:

> SELECT ucase('SparkSql');
 SPARKSQL
unbase64
unbase64(str) - Converts the argument from a base  stringstrto a binary.

Examples:

> SELECT unbase64('U3BhcmsgU1FM');
 Spark SQL
unhex
unhex(expr) - Converts hexadecimalexprto binary.

Examples:

> SELECT decode(unhex('537061726B2053514C'), 'UTF-8');
 Spark SQL
unix_timestamp
unix_timestamp([expr[, pattern]]) - Returns the UNIX timestamp of current or specified time.

Examples:

> SELECT unix_timestamp();

> SELECT unix_timestamp('2016-04-08', 'yyyy-MM-dd');

upper
upper(str) - Returnsstrwith all characters changed to uppercase.

Examples:

> SELECT upper('SparkSql');
 SPARKSQL
uuid
uuid() - Returns an universally unique identifier (UUID) string. The value is returned as a canonical UUID -character string.

Examples:

> SELECT uuid();
 46707d92-02f4---a4c3b23e6266
var_pop
var_pop(expr) - Returns the population variance calculated from values of a group.

var_samp
var_samp(expr) - Returns the sample variance calculated from values of a group.

variance
variance(expr) - Returns the sample variance calculated from values of a group.

weekofyear
weekofyear(date) - Returns the week of the year of the given date. A week is considered to start on a Monday and week  is the first week with > days.

Examples:

> SELECT weekofyear('2008-02-20');

when
CASE WHEN expr1 THEN expr2 [WHEN expr3 THEN expr4]* [ELSE expr5] END - Whenexpr1= true, returnsexpr2; whenexpr3= true, returnexpr4; else returnexpr5.

window
xpath
xpath(xml, xpath) - Returns a string array of values within the nodes of xml that match the XPath expression.

Examples:

> SELECT xpath('b1b2b3c1c2','a/b/text()');
 ['b1','b2','b3']
xpath_boolean
xpath_boolean(xml, xpath) - Returns true if the XPath expression evaluates to true, or if a matching node is found.

Examples:

> SELECT xpath_boolean('','a/b');
 true
xpath_double
xpath_double(xml, xpath) - Returns a double value, the value zero if no match is found, or NaN if a match is found but the value is non-numeric.

Examples:

> SELECT xpath_double('', 'sum(a/b)');
 3.0
xpath_float
xpath_float(xml, xpath) - Returns a float value, the value zero if no match is found, or NaN if a match is found but the value is non-numeric.

Examples:

> SELECT xpath_float('', 'sum(a/b)');
 3.0
xpath_int
xpath_int(xml, xpath) - Returns an integer value, or the value zero if no match is found, or a match is found but the value is non-numeric.

Examples:

> SELECT xpath_int('', 'sum(a/b)');

xpath_long
xpath_long(xml, xpath) - Returns a long integer value, or the value zero if no match is found, or a match is found but the value is non-numeric.

Examples:

> SELECT xpath_long('', 'sum(a/b)');

xpath_number
xpath_number(xml, xpath) - Returns a double value, the value zero if no match is found, or NaN if a match is found but the value is non-numeric.

Examples:

> SELECT xpath_number('', 'sum(a/b)');
 3.0
xpath_short
xpath_short(xml, xpath) - Returns a short integer value, or the value zero if no match is found, or a match is found but the value is non-numeric.

Examples:

> SELECT xpath_short('', 'sum(a/b)');

xpath_string
xpath_string(xml, xpath) - Returns the text contents of the first xml node that matches the XPath expression.

Examples:

> SELECT xpath_string('bcc','a/c');
 cc
year
year(date) - Returns the year component of the date/timestamp.

Examples:

> SELECT year('2016-07-30');

|
expr1 | expr2 - Returns the result of bitwise OR ofexpr1andexpr2.

Examples:

> SELECT  | ;

~
~ expr - Returns the result of bitwise NOT ofexpr.

Examples:

> SELECT ~ ;
 -

参考https://www.2cto.com/net/201803/727248.html