首页 > 解决方案 > 如何查询 AWS Athena 分区表

问题描述

问题摘要

当我尝试SELECT使用子句查询分区表时WHERE,Athena 产生错误。

log我的表中有 4 种类型的分区。

我尝试SELECT对分区表进行查询。但收到以下错误消息。

错误信息

GENERIC_INTERNAL_ERROR: No value present
This query ran against the "default" database, unless qualified by the query.

我尝试过的 SELECT 查询

SELECT *
FROM logs
WHERE year='2020'
  AND month='10'
  AND day ='05';

SELECT *
FROM "default"."logs"
WHERE year='2020'
  AND month='10'
  AND day ='05';

由于有关 的错误消息No value present,我检查了分区结果。

SHOW PARTITIONS logs;

结果

year=2020/month=10/day=05/hour=17
year=2020/month=10/day=05/hour=11
year=2020/month=10/day=05/hour=19
year=2020/month=10/day=05/hour=04
year=2020/month=10/day=05/hour=18
year=2020/month=10/day=05/hour=15
year=2020/month=10/day=05/hour=14
year=2020/month=10/day=05/hour=16
year=2020/month=10/day=05/hour=13
year=2020/month=10/day=05/hour=21
year=2020/month=10/day=05/hour=05
year=2020/month=10/day=05/hour=08
year=2020/month=10/day=05/hour=20
year=2020/month=10/day=05/hour=12
year=2020/month=10/day=05/hour=03
year=2020/month=10/day=05/hour=01
year=2020/month=10/day=05/hour=10
year=2020/month=10/day=05/hour=02
year=2020/month=10/day=05/hour=09
year=2020/month=10/day=05/hour=22
year=2020/month=10/day=05/hour=23
year=2020/month=10/day=05/hour=06
year=2020/month=10/day=05/hour=07
year=2020/month=10/day=05/hour=00
year=2020/month=10/day=04/hour=00

非常感谢您的帮助。


更多信息

CREATE TABLE我使用的命令

创建表

CREATE EXTERNAL TABLE `logs`(
  `date` date, 
  `time` string, 
  `location` string, 
  `bytes` bigint, 
  `request_ip` string, 
  `method` string, 
  `host` string, 
  `uri` string, 
  `status` int, 
  `referrer` string, 
  `user_agent` string, 
  `query_string` string, 
  `cookie` string, 
  `result_type` string, 
  `request_id` string, 
  `host_header` string, 
  `request_protocol` string, 
  `request_bytes` bigint, 
  `time_taken` float, 
  `xforwarded_for` string, 
  `ssl_protocol` string, 
  `ssl_cipher` string, 
  `response_result_type` string, 
  `http_version` string, 
  `fle_status` string, 
  `fle_encrypted_fields` int)
PARTITIONED BY ( 
  `year` string, 
  `month` string, 
  `day` string, 
  `hour` string)
ROW FORMAT DELIMITED 
  FIELDS TERMINATED BY '\t' 
WITH SERDEPROPERTIES ( 
  'input.regex'='^(?!#)([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)\\\\s+([^ \\\\t]+)$') 
STORED AS INPUTFORMAT 
  'org.apache.hadoop.mapred.TextInputFormat' 
OUTPUTFORMAT 
  'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION
  's3://mybucket/path'
TBLPROPERTIES (
  'projection.date.format'='yyyy/MM/dd', 
  'projection.date.interval'='1', 
  'projection.date.interval.unit'='DAYS', 
  'projection.date.range'='2019/11/27, NOW-1DAYS', 
  'projection.date.type'='date', 
  'projection.day.type'='string', 
  'projection.enabled'='true', 
  'projection.hour.type'='string', 
  'projection.month.type'='string', 
  'projection.year.type'='string', 
  'skip.header.line.count'='2', 
  'storage.location.template'='s3://mybucket/path/distributionID/${year}/${month}/${day}/${hour}/', 
  'transient_lastDdlTime'='1575005094')

标签: amazon-web-servicesamazon-athenapartition

解决方案


您的表使用分区投影,但您的配置与分区不匹配。分区投影是一个相当新的功能,文档仍有一些不足之处,所以我完全理解它令人困惑。我想我明白你在做什么。

分区投影配置必须与表的分区键完全匹配。在您的情况下,表有四个分区键,分区投影配置提到了五个。除了四种类型错误之外,没有string分区投影类型。

您可以通过进行两项更改来解决此问题。首先像这样更改分区键:

PARTITIONED BY (
  `date` string,
  `hour` string
)

这将删除“年”、“月”和“日”分区键,取而代之的是“日期”键。没有必要仅仅因为它们是单独的“目录”而拥有单独的日期组件,并且仅仅拥有一个“日期”键将使查询更容易编写。

然后将表属性更改为:

TBLPROPERTIES (
  'projection.date.format' = 'yyyy/MM/dd', 
  'projection.date.interval' = '1', 
  'projection.date.interval.unit' = 'DAYS', 
  'projection.date.range' = '2019/11/27, NOW-1DAYS', 
  'projection.date.type' = 'date', 
  'projection.hour.type' = 'integer',
  'projection.hour.range' = '0-23',
  'projection.hour.digits' = '2'
  'projection.enabled' = 'true',
  'storage.location.template'='s3://mybucket/path/distributionID/${date}/${hour}/', 
  'skip.header.line.count' = '2'
)

这告诉 Athena “日期”分区键的类型为date,并且它的格式为“YYYY/MM/DD”(对应于 S3 URI 中的格式,这很重要)。它还告诉 Athena,“小时”分区键是一个integer范围为 0-23 的分区键,格式为两位数(即填充零)。最后,它指定这些分区键如何映射到 S3 上的分区位置。当查询中的日期为“2020/10/06”时,该字符串将逐字插入位置模板中。

通过这些更改,您应该能够运行如下查询(“日期”是保留字,当它是列名时必须引用):

SELECT *
FROM logs
WHERE "date" = '2020/10/06'
SELECT *
FROM logs
WHERE "date" BETWEEN '2020/10/01' AND '2020/10/06'
AND hour BETWEEN 9 AND 21

请注意,日期格式必须与分区投影配置中的格式完全相同,即YYYY/MM/DD.


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