Functions and Operators部分阅读记录【presto官网官网文档】
2021-12-18 17:49
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版本：0.266
[TOC]
1 Comparison Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/comparison.html
is distinct from
presto:default> select 3 is distinct from 3; _col0 ------- false (1 row) Query 20211214_012451_00004_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 164ms [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select 3 is not distinct from 3; _col0 ------- true (1 row) Query 20211214_013715_00012_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select null is distinct from null; _col0 ------- false (1 row) Query 20211214_013739_00013_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 247ms [0 rows, 0B] [0 rows/s, 0B/s]
greatest/least
presto:default> select greatest(1,2,3,4); _col0 ------- 4 (1 row) Query 20211214_012648_00005_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 387ms [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select least(1,2,3,4); _col0 ------- 1 (1 row) Query 20211214_013817_00014_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 175ms [0 rows, 0B] [0 rows/s, 0B/s]
any/all/some
presto:default> select 'hello' = any(values 'hello','world'); _col0 ------- true (1 row) Query 20211214_012811_00006_dd2sy, FINISHED, 1 node Splits: 67 total, 67 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select 21 < all(values 19,20,21); _col0 ------- false (1 row) Query 20211214_012831_00007_dd2sy, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select 42 >= some(select 41 union all select 42 union all select 43); _col0 ------- true (1 row) Query 20211214_012906_00009_dd2sy, FINISHED, 1 node Splits: 85 total, 85 done (100.00%) 489ms [0 rows, 0B] [0 rows/s, 0B/s]
like
presto:default> select * from (values('abc'),('_cd'),('cde')) as t(name) where name like '%#_%' escape '#';
name
------
_cd
(1 row)
Query 20211214_014124_00015_dd2sy, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto:default> select * from (values('a%c'),('%cd'),('cde')) as t(name) where name like '%#%%' escape '#';
name
------
a%c
%cd
(2 rows)
Query 20211214_014226_00016_dd2sy, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
403ms [0 rows, 0B] [0 rows/s, 0B/s]
2 Conditional Expressions
来自官网：https://prestodb.io/docs/current/functions/conditional.html
if
presto:default> select if(3>2,1); _col0 ------- 1 (1 row) Query 20211214_014557_00018_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 224ms [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select if(3<2,1,0); _col0 ------- 0 (1 row) Query 20211214_014604_00019_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 158ms [0 rows, 0B] [0 rows/s, 0B/s]
nullif
presto:default> select nullif(2,2); _col0 ------- NULL (1 row) Query 20211214_015025_00021_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select nullif(2,3); _col0 ------- 2 (1 row) Query 20211214_015031_00022_dd2sy, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 339ms [0 rows, 0B] [0 rows/s, 0B/s]
try
hive (default)> create table shipping(
> origin_state string,
> origin_zip string,
> packages string,
> total_cost string
> );
OK
Time taken: 3.18 seconds
hive (default)> insert into shipping values ('California','94131','25','100'),('California','P332a','5','72'),('California','94025','0','155'),('New Jersey','08544','225','490');
Query ID = root_20211214095954_10726f03-d2e4-4e63-b340-59d06a382b08
Total jobs = 1
Launching Job 1 out of 1
Status: Running (Executing on YARN cluster with App id application_1639444902055_0001)
--------------------------------------------------------------------------------
VERTICES STATUS TOTAL COMPLETED RUNNING PENDING FAILED KILLED
--------------------------------------------------------------------------------
Map 1 .......... SUCCEEDED 1 1 0 0 0 0
--------------------------------------------------------------------------------
VERTICES: 01/01 [==========================>>] 100% ELAPSED TIME: 6.65 s
--------------------------------------------------------------------------------
Loading data to table default.shipping
Table default.shipping stats: [numFiles=1, numRows=4, totalSize=94, rawDataSize=90]
OK
values__tmp__table__1.tmp_values_col1 values__tmp__table__1.tmp_values_col2 values__tmp__table__1.tmp_values_col3 values__tmp__table__1.tmp_values_col4
Time taken: 12.083 seconds
hive (default)> select * from shipping;
OK
shipping.origin_state shipping.origin_zip shipping.packages shipping.total_cost
California 94131 25 100
California P332a 5 72
California 94025 0 155
New Jersey 08544 225 490
Time taken: 0.117 seconds, Fetched: 4 row(s)
presto:default> select cast(origin_zip as bigint) from shipping;
Query 20211214_020812_00005_geiez, FAILED, 1 node
Splits: 17 total, 0 done (0.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
Query 20211214_020812_00005_geiez failed: Cannot cast 'P332a' to BIGINT
presto:default> select try(cast(origin_zip as bigint)) from shipping;
_col0
-------
94131
NULL
94025
8544
(4 rows)
Query 20211214_020833_00007_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [4 rows, 94B] [7 rows/s, 181B/s]
presto:default> select cast(total_cost as integer)/cast(packages as integer) as per_package from shipping;
Query 20211214_021355_00009_geiez, FAILED, 1 node
Splits: 17 total, 0 done (0.00%)
348ms [0 rows, 0B] [0 rows/s, 0B/s]
Query 20211214_021355_00009_geiez failed: / by zero
presto:default> select coalesce(try(cast(total_cost as integer)/cast(packages as integer)),0) as per_package from shipping;
per_package
-------------
4
14
0
2
(4 rows)
Query 20211214_021501_00010_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
408ms [4 rows, 94B] [9 rows/s, 230B/s]
3 Lambda Expressions
来自官网：https://prestodb.io/docs/current/functions/lambda.html
presto:default> select filter(array[5,-6,1,7],x->x>0); _col0 ----------- [5, 1, 7] (1 row) Query 20211214_022535_00015_geiez, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto:default> select filter(array[5,-6,1,7],x->sum(x)); Query 20211214_022605_00016_geiez failed: line 1:34: Lambda expression cannot contain aggregations, window functions or grouping operations: ["sum"(x)] select filter(array[5,-6,1,7],x->sum(x)) presto:default> select filter(array[5,-6,1,7],x->x+(select 3)); Query 20211214_022626_00017_geiez failed: line 1:36: Lambda expression cannot contain subqueries select filter(array[5,-6,1,7],x->x+(select 3))
4 Conversion Functions
来自官网：https://prestodb.io/docs/current/functions/conversion.html
cast/try_cast
presto:default> desc shipping; Column | Type | Extra | Comment --------------+---------+-------+--------- origin_state | varchar | | origin_zip | varchar | | packages | varchar | | total_cost | varchar | | (4 rows) Query 20211214_022837_00018_geiez, FINISHED, 1 node Splits: 19 total, 19 done (100.00%) 0:01 [4 rows, 284B] [3 rows/s, 267B/s] presto:default> select total_cost+1 from shipping; Query 20211214_022851_00019_geiez failed: line 1:18: '+' cannot be applied to varchar, integer select total_cost+1 from shipping presto:default> select cast(total_cost as integer) from shipping; _col0 ------- 100 72 155 490 (4 rows) Query 20211214_023102_00020_geiez, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 329ms [4 rows, 94B] [12 rows/s, 286B/s] presto:default> select try_cast(origin_state as integer) from shipping; _col0 ------- NULL NULL NULL NULL (4 rows) Query 20211214_023453_00030_geiez, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [4 rows, 94B] [6 rows/s, 151B/s]
parse_presto_data_size
presto:default> select parse_presto_data_size('1b');
Query 20211214_023210_00021_geiez failed: Invalid data size: '1b'
presto:default> select parse_presto_data_size('1B');
_col0
-------
1
(1 row)
Query 20211214_023226_00022_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
281ms [0 rows, 0B] [0 rows/s, 0B/s]
presto:default> select parse_presto_data_size('1KB');
Query 20211214_023231_00023_geiez failed: Invalid data size: '1KB'
presto:default> select parse_presto_data_size('1kB');
_col0
-------
1024
(1 row)
Query 20211214_023234_00024_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
150ms [0 rows, 0B] [0 rows/s, 0B/s]
presto:default> select parse_presto_data_size('2.3mB');
Query 20211214_023242_00025_geiez failed: Invalid data size: '2.3mB'
presto:default> select parse_presto_data_size('2.3MB');
_col0
---------
2411724
(1 row)
Query 20211214_023250_00026_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
150ms [0 rows, 0B] [0 rows/s, 0B/s]
typeof
presto:default> select typeof(12);
_col0
---------
integer
(1 row)
Query 20211214_023332_00027_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
161ms [0 rows, 0B] [0 rows/s, 0B/s]
presto:default> select typeof('cat');
_col0
------------
varchar(3)
(1 row)
Query 20211214_023338_00028_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
116ms [0 rows, 0B] [0 rows/s, 0B/s]
presto:default> select typeof(cos(2)+1.5);
_col0
--------
double
(1 row)
Query 20211214_023349_00029_geiez, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
173ms [0 rows, 0B] [0 rows/s, 0B/s]
5 Mathematical Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/math.html
presto> select truncate(12.3); _col0 ------- 12 (1 row) Query 20211215_121436_00002_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select truncate(12.7); _col0 ------- 12 (1 row) Query 20211215_121441_00003_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 179ms [0 rows, 0B] [0 rows/s, 0B/s] # 去掉小数点右边的 1 个数字 presto> select truncate(12.123,1); _col0 -------- 12.100 (1 row) Query 20211215_121527_00006_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 177ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select truncate(12.123,2); _col0 -------- 12.120 (1 row) Query 20211215_121500_00004_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select truncate(12.123,3); _col0 -------- 12.123 (1 row) Query 20211215_121519_00005_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 324ms [0 rows, 0B] [0 rows/s, 0B/s] # 去掉小数点左边的 1 个数字 presto> select truncate(12.123,-1); _col0 -------- 10.000 (1 row) Query 20211215_121732_00008_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select truncate(12.123,-2); _col0 ------- 0.000 (1 row) Query 20211215_121752_00009_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 331ms [0 rows, 0B] [0 rows/s, 0B/s]
6 Bitwise Functions
# bit_count(x, bits) bits??
7 Decimal Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/decimal.html
# decimal(n,m) # n -> precision # m -> scale presto> create table hive.default.decimal_t(d decimal(10,5)); CREATE TABLE presto> insert into hive.default.decimal_t values (12345.12345); INSERT: 1 row Query 20211215_123422_00016_vfvk7, FINISHED, 3 nodes Splits: 53 total, 53 done (100.00%) 0:07 [0 rows, 0B] [0 rows/s, 0B/s] presto> insert into hive.default.decimal_t values (12345.1234); INSERT: 1 row Query 20211215_123434_00017_vfvk7, FINISHED, 3 nodes Splits: 69 total, 69 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select * from hive.default.decimal_t; d ------------- 12345.12340 12345.12345 (2 rows) Query 20211215_123443_00018_vfvk7, FINISHED, 3 nodes Splits: 18 total, 18 done (100.00%) 0:02 [2 rows, 571B] [0 rows/s, 253B/s] presto> select d*2 from hive.default.decimal_t; _col0 ------------- 24690.24680 24690.24690 (2 rows) Query 20211215_123649_00020_vfvk7, FINISHED, 2 nodes Splits: 18 total, 18 done (100.00%) 0:02 [2 rows, 571B] [1 rows/s, 346B/s] presto> select -d from hive.default.decimal_t; _col0 -------------- -12345.12340 -12345.12345 (2 rows) Query 20211215_123709_00021_vfvk7, FINISHED, 2 nodes Splits: 18 total, 18 done (100.00%) 0:01 [2 rows, 571B] [2 rows/s, 783B/s]
8 String Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/string.html
String Operators
presto> select * from hive.default.student; id | name ----+---------- 1 | zhangsan 2 | lisi (2 rows) Query 20211215_123840_00027_vfvk7, FINISHED, 2 nodes Splits: 18 total, 18 done (100.00%) 0:01 [2 rows, 18B] [1 rows/s, 15B/s] presto> select name || '-male' from hive.default.student; _col0 --------------- lisi-male zhangsan-male (2 rows) Query 20211215_123901_00028_vfvk7, FINISHED, 2 nodes Splits: 18 total, 18 done (100.00%) 0:01 [2 rows, 18B] [3 rows/s, 30B/s]
String Functions
presto> select chr(123);
_col0
-------
{
(1 row)
Query 20211215_124149_00031_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
128ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select concat(name,'-male') from hive.default.student;
_col0
---------------
zhangsan-male
lisi-male
(2 rows)
Query 20211215_124252_00032_vfvk7, FINISHED, 2 nodes
Splits: 18 total, 18 done (100.00%)
0:01 [2 rows, 18B] [3 rows/s, 30B/s]
presto> select lpad(name,10,'abc') from hive.default.student;
_col0
------------
abzhangsan
abcabclisi
(2 rows)
Query 20211215_124630_00036_vfvk7, FINISHED, 2 nodes
Splits: 18 total, 18 done (100.00%)
0:01 [2 rows, 18B] [1 rows/s, 16B/s]
presto> select length(ltrim(' aa '));
_col0
-------
3
(1 row)
Query 20211215_124735_00039_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
143ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select replace('abcd','a');
_col0
-------
bcd
(1 row)
Query 20211215_124822_00040_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
133ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select replace('abcd','a','e');
_col0
-------
ebcd
(1 row)
Query 20211215_124828_00041_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
265ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split('a|b|c','|');
_col0
-----------
[a, b, c]
(1 row)
Query 20211215_124900_00042_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
289ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split('a|b|c','|',3);
_col0
-----------
[a, b, c]
(1 row)
Query 20211215_124922_00043_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
182ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split('a|b|c','|',2);
_col0
----------
[a, b|c]
(1 row)
Query 20211215_124924_00044_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
141ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_part('a|b|c','|',1);
_col0
-------
a
(1 row)
Query 20211215_125015_00046_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
271ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_part('a|b|c','|',2);
_col0
-------
b
(1 row)
Query 20211215_125020_00047_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
212ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_to_map('a-1|b-2|c-3','|','-');
_col0
-----------------
{a=1, b=2, c=3}
(1 row)
Query 20211215_125307_00048_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
467ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_to_map('a-1|b-2|c-3|a-2','|','-',(k,v1,v2)->v2);
_col0
-----------------
{a=2, b=2, c=3}
(1 row)
Query 20211215_125441_00050_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
229ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_to_map('a-1|b-2|c-3|a-2','|','-',(k,v1,v2)->concat(v1,v2));
_col0
------------------
{a=12, b=2, c=3}
(1 row)
Query 20211215_125450_00051_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
146ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select split_to_multimap('a-1|b-2|c-3|a-2','|','-');
_col0
--------------------------
{a=[1, 2], b=[2], c=[3]}
(1 row)
Query 20211215_125606_00052_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
164ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select strpos('abedab','ab');
_col0
-------
1
(1 row)
Query 20211215_125737_00053_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select strpos('abedab','ab',2);
_col0
-------
5
(1 row)
Query 20211215_125747_00054_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
180ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select position('ab' in 'abedab');
_col0
-------
1
(1 row)
Query 20211215_125823_00055_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
207ms [0 rows, 0B] [0 rows/s, 0B/s]
Unicode Functions
9 Regular Expression Functions
来自官网：https://prestodb.io/docs/current/functions/regexp.html
原文含有示例
10 Binary Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/binary.html
11 JSON Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/json.html
原文含有示例
12 Date and Time Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/datetime.html
Date and Time Operators
原文含有示例
Time Zone Conversion
原文含有示例
Date and Time Functions
presto> select localtime; _col0 -------------- 21:18:54.720 (1 row) Query 20211215_131854_00061_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 401ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select current_time ; _col0 ---------------------------- 21:19:08.666 Asia/Shanghai (1 row) Query 20211215_131908_00062_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 256ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select current_timestamp; _col0 --------------------------------------- 2021-12-15 21:19:26.236 Asia/Shanghai (1 row) Query 20211215_131926_00063_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 244ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select current_date ; _col0 ------------ 2021-12-15 (1 row) Query 20211215_131939_00064_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 422ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select to_milliseconds(interval '2' day); _col0 ----------- 172800000 (1 row) Query 20211215_132123_00066_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 218ms [0 rows, 0B] [0 rows/s, 0B/s]
Truncation Function
原文含有示例
Interval Functions
presto> select date_add('day',2,timestamp '2012-08-08 00:00');
_col0
-------------------------
2012-08-10 00:00:00.000
(1 row)
Query 20211215_132509_00068_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
157ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select date_diff('day',timestamp '2012-08-08 00:00',timestamp '2012-08-10 00:00');
_col0
-------
2
(1 row)
Query 20211215_132600_00070_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
204ms [0 rows, 0B] [0 rows/s, 0B/s]
Duration Function
原文含有示例
presto> select date_format(current_timestamp,'%a');
_col0
--------
星期三
(1 row)
Query 20211215_133023_00072_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
168ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select date_format(current_timestamp,'%c');
_col0
-------
12
(1 row)
Query 20211215_133038_00073_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
165ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select date_parse('2012-08-08','%Y-%m-%d');
_col0
-------------------------
2012-08-08 00:00:00.000
(1 row)
Query 20211215_133856_00081_vfvk7, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
319ms [0 rows, 0B] [0 rows/s, 0B/s]
Java Date Functions
TODO
Extraction Function
presto> select extract(year from timestamp'2012-08-08'); _col0 ------- 2012 (1 row) Query 20211215_134139_00085_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select year(timestamp'2012-08-08'); _col0 ------- 2012 (1 row) Query 20211215_134211_00087_vfvk7, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 163ms [0 rows, 0B] [0 rows/s, 0B/s]
Convenience Extraction Functions
TODO
13 Aggregate Functions
来自官网：https://prestodb.io/docs/current/functions/aggregate.html
General Aggregate Functions
presto> select count(*) from (values 1,2,null,3) as t(id); _col0 ------- 4 (1 row) Query 20211218_015350_00021_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 345ms [0 rows, 0B] [0 rows/s, 0B/s] # count(x) → bigint # Returns the number of non-null input values. presto> select count(id) from (values 1,2,null,3) as t(id); _col0 ------- 3 (1 row) Query 20211218_015154_00020_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 215ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select sum(id) from (values 1,2,null,3) as t(id); _col0 ------- 6 (1 row) Query 20211218_012656_00002_kjjye, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 0:04 [0 rows, 0B] [0 rows/s, 0B/s] presto> select avg(id) from (values 1,2,null,3) as t(id); _col0 ------- 2.0 (1 row) Query 20211218_012916_00005_kjjye, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_agg(id) from (values 1,2,3,4) as t(id); _col0 -------------- [1, 2, 3, 4] (1 row) Query 20211218_013410_00006_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 0:02 [0 rows, 0B] [0 rows/s, 0B/s] presto> select array_agg(id order by id desc) from (values 1,2,3,4) as t(id); _col0 -------------- [4, 3, 2, 1] (1 row) Query 20211218_023046_00046_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 387ms [0 rows, 0B] [0 rows/s, 0B/s]
# avg(time interval type) → time interval type# # Returns the average interval length of all input values. # 支持 avg(interval day to second) , avg(interval year to month) 两种类型 # 2 和 3 的均值取 2，小数 0.5 换算到月份上 presto> select avg(time) from (values interval '2-1' year to month,interval '3-1' year to month) as t(time); _col0 ------- 2-7 (1 row) Query 20211218_014727_00017_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select avg(time) from (values interval '2-1' year to month,interval '4-1' year to month) as t(time); _col0 ------- 3-1 (1 row) Query 20211218_014849_00018_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select count_if(id>1) from (values 1,2,0,3) as t(id); _col0 ------- 2 (1 row) Query 20211218_020306_00037_kjjye, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 317ms [0 rows, 0B] [0 rows/s, 0B/s] # 对于多个(x,y)形式的数据，返回最大的y对应的x presto> select max_by(id,cnt) from (values (1,45),(2,11),(3,30)) as t(id,cnt); _col0 ------- 1 (1 row) Query 20211218_020915_00039_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 293ms [0 rows, 0B] [0 rows/s, 0B/s] # 返回前 n 个值 presto> select max_by(id,cnt,2) from (values (1,45),(2,11),(3,30)) as t(id,cnt); _col0 -------- [1, 3] (1 row) Query 20211218_021020_00040_kjjye, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 459ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select max(id,2) from (values 1,2,3) as t(id); _col0 -------- [3, 2] (1 row) Query 20211218_021151_00043_kjjye, FINISHED, 1 node Splits: 18 total, 18 done (100.00%) 417ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> SELECT id, reduce_agg(value, 2, (a, b) -> a + b, (a, b) -> a + b) -> FROM ( -> VALUES -> (1, 2), -> (1, 3), -> (1, 4), -> (2, 20), -> (2, 30), -> (2, 40) -> ) AS t(id, value) -> GROUP BY id; id | _col1 ----+------- 2 | 92 1 | 11 (2 rows) Query 20211218_023252_00047_kjjye, FINISHED, 1 node Splits: 33 total, 33 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select set_agg(id) from (values 1,1,2,2,3,1) as t(id); _col0 ----------- [1, 2, 3] (1 row) Query 20211218_023644_00050_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 236ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select set_union(arrs) from (values array[1,2,3],array[2,3,4]) as t(arrs); _col0 -------------- [1, 2, 3, 4] (1 row) Query 20211218_023759_00052_kjjye, FINISHED, 1 node Splits: 1 total, 1 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s]
Bitwise Aggregate Functions
TODO
Map Aggregate Functions
presto> select histogram(id) from (values 1,1,2,2,3,1) as t(id);
_col0
-----------------
{1=3, 2=2, 3=1}
(1 row)
Query 20211218_023955_00053_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
237ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select map_agg(id,name) from (values (1,'aa'),(2,'bb')) as t(id,name);
_col0
--------------
{1=aa, 2=bb}
(1 row)
Query 20211218_024416_00056_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select map_agg(id,name) from (values (1,'aa'),(2,'bb'),(1,'cc')) as t(id,name);
_col0
--------------
{1=aa, 2=bb}
(1 row)
Query 20211218_025347_00065_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
181ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select multimap_agg(id,name) from (values (1,'aa'),(2,'bb'),(1,'cc')) as t(id,name);
_col0
----------------------
{1=[aa, cc], 2=[bb]}
(1 row)
Query 20211218_025323_00064_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
320ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select map_union(mapp) from (values map(array[1,2],array['aa','bb']),map(array[3,4],array['cc','dd'])) as t(mapp);
_col0
--------------------------
{1=aa, 2=bb, 3=cc, 4=dd}
(1 row)
Query 20211218_024754_00058_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
156ms [0 rows, 0B] [0 rows/s, 0B/s]
# 在这两个 map 中有两个 key 都为 1，返回其对应的值的时候，是随机选择，可能是 'aa'，也可能是 'cc'
presto> select map_union(mapp) from (values map(array[1,2],array['aa','bb']),map(array[1,4],array['cc','dd'])) as t(mapp);
_col0
--------------------
{1=aa, 2=bb, 4=dd}
(1 row)
Query 20211218_024813_00060_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
235ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select map_union_sum(mapp) from (values map(array['aa','bb'],array[1,2]),map(array['aa','cc'],array[2,3])) as t(mapp);
_col0
--------------------
{aa=3, bb=2, cc=3}
(1 row)
Query 20211218_025053_00061_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
422ms [0 rows, 0B] [0 rows/s, 0B/s]
# null被处理成0
presto> select map_union_sum(mapp) from (values map(array['aa','bb'],array[1,2]),map(array['aa','cc'],array[2,null])) as t(mapp);
_col0
--------------------
{aa=3, bb=2, cc=0}
(1 row)
Query 20211218_025119_00062_kjjye, FINISHED, 1 node
Splits: 1 total, 1 done (100.00%)
428ms [0 rows, 0B] [0 rows/s, 0B/s]
Approximate Aggregate Functions
TODO
Statistical Aggregate Functions
TODO
Classification Metrics Aggregate Functions
TODO
Differential Entropy Functions
TODO
14 Window Functions
来自官网：https://prestodb.io/docs/current/functions/window.html
原文含有示例
15 Array Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/array.html
presto> select all_match(array[1,2,3],x->x>0);
_col0
-------
true
(1 row)
Query 20211218_034206_00071_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select any_match(array[1,2,3],x->x>2);
_col0
-------
true
(1 row)
presto> select none_match(array[1,2,3,4],x->x>5);
_col0
-------
true
(1 row)
Query 20211218_042736_00110_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
122ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select none_match(array[1,2,3,4],x->x>2);
_col0
-------
false
(1 row)
Query 20211218_042740_00111_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
143ms [0 rows, 0B] [0 rows/s, 0B/s]
Query 20211218_034349_00072_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
360ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_average(array[1,2,3]);
_col0
-------
2.0
(1 row)
Query 20211218_034425_00073_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_average(array[1,2,3,null]);
_col0
-------
2.0
(1 row)
Query 20211218_034432_00074_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_distinct(array[1,2,3,1]);
_col0
-----------
[1, 2, 3]
(1 row)
Query 20211218_034512_00075_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
180ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_duplicates (array[1,2,3,1]);
_col0
-------
[1]
(1 row)
Query 20211218_034526_00076_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:01 [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_except(array[1,2,3],array[3,4,5]);
_col0
--------
[1, 2]
(1 row)
Query 20211218_034606_00077_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
228ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_except(array[1,2,1,3],array[3,4,5]);
_col0
--------
[1, 2]
(1 row)
Query 20211218_034711_00079_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
116ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_frequency(array[1,2,1,3]);
_col0
-----------------
{1=2, 2=1, 3=1}
(1 row)
Query 20211218_034804_00080_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
325ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_join(array['a','b',null],'-','str');
_col0
---------
a-b-str
(1 row)
Query 20211218_034954_00081_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
173ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_max(array[1,2,1,3]);
_col0
-------
3
(1 row)
Query 20211218_035647_00083_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
269ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_position(array['bb','aa','bb'],'bb');
_col0
-------
1
(1 row)
Query 20211218_035836_00087_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
129ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_position(array['bb','aa','bb'],'bb',2);
_col0
-------
3
(1 row)
Query 20211218_035917_00088_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
217ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_position(array['bb','aa','bb'],'bb',-2);
_col0
-------
1
(1 row)
Query 20211218_035930_00089_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
159ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_remove(array['bb','aa','bb'],'bb');
_col0
-------
[aa]
(1 row)
Query 20211218_040009_00090_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
188ms [0 rows, 0B] [0 rows/s, 0B/s]
presto> select array_sort(array['bb','aa','bb']);
_col0
--------------
[aa, bb, bb]
(1 row)
Query 20211218_040031_00091_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
208ms [0 rows, 0B] [0 rows/s, 0B/s]
SELECT array_sort(ARRAY [3, 2, 5, 1, 2], (x, y) -> IF(x < y, 1, IF(x = y, 0, -1))); -- [5, 3, 2, 2, 1] SELECT array_sort(ARRAY ['bc', 'ab', 'dc'], (x, y) -> IF(x < y, 1, IF(x = y, 0, -1))); -- ['dc', 'bc', 'ab'] SELECT array_sort(ARRAY [3, 2, null, 5, null, 1, 2], -- sort null first with descending order (x, y) -> CASE WHEN x IS NULL THEN -1 WHEN y IS NULL THEN 1 WHEN x < y THEN 1 WHEN x = y THEN 0 ELSE -1 END); -- [null, null, 5, 3, 2, 2, 1] SELECT array_sort(ARRAY [3, 2, null, 5, null, 1, 2], -- sort null last with descending order (x, y) -> CASE WHEN x IS NULL THEN 1 WHEN y IS NULL THEN -1 WHEN x < y THEN 1 WHEN x = y THEN 0 ELSE -1 END); -- [5, 3, 2, 2, 1, null, null] SELECT array_sort(ARRAY ['a', 'abcd', 'abc'], -- sort by string length (x, y) -> IF(length(x) < length(y), -1, IF(length(x) = length(y), 0, 1))); -- ['a', 'abc', 'abcd'] SELECT array_sort(ARRAY [ARRAY[2, 3, 1], ARRAY[4, 2, 1, 4], ARRAY[1, 2]], -- sort by array length (x, y) -> IF(cardinality(x) < cardinality(y), -1, IF(cardinality(x) = cardinality(y), 0, 1))); -- [[1, 2], [2, 3, 1], [4, 2, 1, 4]]
presto> select array_sum(array[1,2,1,3]); _col0 ------- 7 (1 row) Query 20211218_041207_00092_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 220ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select array_sum(array[null,null]); _col0 ------- 0 (1 row) Query 20211218_041214_00093_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 243ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select array_sum(array[1,2,1,3,null]); _col0 ------- 7 (1 row) Query 20211218_041221_00094_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 145ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select array_union(array[1,2,3],array[3,4,5]); _col0 ----------------- [1, 2, 3, 4, 5] (1 row) Query 20211218_041620_00098_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 204ms [0 rows, 0B] [0 rows/s, 0B/s] # 数组大小 presto> select cardinality(array[1,2,3]); _col0 ------- 3 (1 row) Query 20211218_041647_00099_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 110ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select concat(array[1,2,3],array[3,4,5]); _col0 -------------------- [1, 2, 3, 3, 4, 5] (1 row) Query 20211218_041837_00102_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 224ms [0 rows, 0B] [0 rows/s, 0B/s] # 数组元素两两组合，第二个参数不能大于5 presto> SELECT combinations(ARRAY['foo', 'bar', 'boo'],2); _col0 -------------------------------------- [[foo, bar], [foo, boo], [bar, boo]] (1 row) Query 20211218_042021_00103_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 158ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select element_at(array['foo', 'bar', 'boo'],1); _col0 ------- foo (1 row) Query 20211218_042207_00105_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 97ms [0 rows, 0B] [0 rows/s, 0B/s] presto> SELECT filter(ARRAY [5, -6, NULL, 7], x -> x > 0); _col0 -------- [5, 7] (1 row) Query 20211218_042239_00106_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 145ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select flatten(array[array[1,2],array[3,4]]); _col0 -------------- [1, 2, 3, 4] (1 row) Query 20211218_042350_00107_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 155ms [0 rows, 0B] [0 rows/s, 0B/s]
SELECT ngrams(ARRAY['foo', 'bar', 'baz', 'foo'], 2); -- [['foo', 'bar'], ['bar', 'baz'], ['baz', 'foo']] SELECT ngrams(ARRAY['foo', 'bar', 'baz', 'foo'], 3); -- [['foo', 'bar', 'baz'], ['bar', 'baz', 'foo']] SELECT ngrams(ARRAY['foo', 'bar', 'baz', 'foo'], 4); -- [['foo', 'bar', 'baz', 'foo']] SELECT ngrams(ARRAY['foo', 'bar', 'baz', 'foo'], 5); -- [['foo', 'bar', 'baz', 'foo']] SELECT ngrams(ARRAY[1, 2, 3, 4], 2); -- [[1, 2], [2, 3], [3, 4]] SELECT reduce(ARRAY [], 0, (s, x) -> s + x, s -> s); -- 0 SELECT reduce(ARRAY [5, 20, 50], 0, (s, x) -> s + x, s -> s); -- 75 SELECT reduce(ARRAY [5, 20, NULL, 50], 0, (s, x) -> s + x, s -> s); -- NULL SELECT reduce(ARRAY [5, 20, NULL, 50], 0, (s, x) -> s + COALESCE(x, 0), s -> s); -- 75 SELECT reduce(ARRAY [5, 20, NULL, 50], 0, (s, x) -> IF(x IS NULL, s, s + x), s -> s); -- 75 SELECT reduce(ARRAY [2147483647, 1], CAST (0 AS BIGINT), (s, x) -> s + x, s -> s); -- 2147483648 SELECT reduce(ARRAY [5, 6, 10, 20], -- calculates arithmetic average: 10.25 CAST(ROW(0.0, 0) AS ROW(sum DOUBLE, count INTEGER)), (s, x) -> CAST(ROW(x + s.sum, s.count + 1) AS ROW(sum DOUBLE, count INTEGER)), s -> IF(s.count = 0, NULL, s.sum / s.count));
presto> select repeat(1,2); _col0 -------- [1, 1] (1 row) Query 20211218_043222_00112_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 197ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select reverse(array[1,2,3,4]); _col0 -------------- [4, 3, 2, 1] (1 row) Query 20211218_043245_00113_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 91ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select sequence(2,5); _col0 -------------- [2, 3, 4, 5] (1 row) Query 20211218_043309_00114_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 108ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select sequence(DATE '2001-08-22',DATE '2011-08-22',INTERVAL '2' year); _col0 -------------------------------------------------------------------------- [2001-08-22, 2003-08-22, 2005-08-22, 2007-08-22, 2009-08-22, 2011-08-22] (1 row) Query 20211218_094414_00133_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 0:01 [0 rows, 0B] [0 rows/s, 0B/s] presto> select slice(array['aa','bb','cc'],1,2); _col0 ---------- [aa, bb] (1 row) Query 20211218_044013_00122_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 127ms [0 rows, 0B] [0 rows/s, 0B/s] presto> select slice(array['aa','bb','cc'],-2,2); _col0 ---------- [bb, cc] (1 row) Query 20211218_044144_00127_kjjye, FINISHED, 1 node Splits: 17 total, 17 done (100.00%) 122ms [0 rows, 0B] [0 rows/s, 0B/s]
SELECT transform(ARRAY [], x -> x + 1); -- [] SELECT transform(ARRAY [5, 6], x -> x + 1); -- [6, 7] SELECT transform(ARRAY [5, NULL, 6], x -> COALESCE(x, 0) + 1); -- [6, 1, 7] SELECT transform(ARRAY ['x', 'abc', 'z'], x -> x || '0'); -- ['x0', 'abc0', 'z0'] SELECT transform(ARRAY [ARRAY [1, NULL, 2], ARRAY[3, NULL]], a -> filter(a, x -> x IS NOT NULL)); -- [[1, 2], [3]]
presto> SELECT zip(ARRAY[1, 2], ARRAY['1b', null, '3b']);
_col0
----------------------------------------------------------------------------
[{field0=1, field1=1b}, {field0=2, field1=null}, {field0=null, field1=3b}]
(1 row)
Query 20211218_044245_00128_kjjye, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
452ms [0 rows, 0B] [0 rows/s, 0B/s]
-- 指定形式
SELECT zip_with(ARRAY[1, 3, 5], ARRAY['a', 'b', 'c'], (x, y) -> (y, x)); -- [ROW('a', 1), ROW('b', 3), ROW('c', 5)]
SELECT zip_with(ARRAY[1, 2], ARRAY[3, 4], (x, y) -> x + y); -- [4, 6]
SELECT zip_with(ARRAY['a', 'b', 'c'], ARRAY['d', 'e', 'f'], (x, y) -> concat(x, y)); -- ['ad', 'be', 'cf']
SELECT zip_with(ARRAY['a'], ARRAY['d', null, 'f'], (x, y) -> coalesce(x, y)); -- ['a', null, 'f']
16 Map Functions and Operators
来自官网：https://prestodb.io/docs/current/functions/map.html
原文含示例
思路类似array
17 URL Functions
TODO
18 IP Functions
19 Geospatial Functions
20 HyperLogLog Functions
21 KHyperLogLog Functions
22 Quantile Digest Functions
23 Color Functions
24 Session Information
25 Teradata Functions
26 Internationalization Functions
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