AWS Athena

https://docs.aws.amazon.com/athena/latest/ug/functions-operators-reference-section.html

light sensor

from the light sensor data project:

CREATE EXTERNAL TABLE IF NOT EXISTS lightsensordb.sensordatatable (
  `timestamp` int,
  `reading1` float,
  `reading2` float 
)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe'
WITH SERDEPROPERTIES (
  'serialization.format' = ' ',
  'field.delim' = ' ',
  'collection.delim' = 'undefined',
  'mapkey.delim' = 'undefined'
) LOCATION 's3://mymainsqueeze/sensor/'
TBLPROPERTIES (
 'has_encrypted_data'='false');

SELECT timestamp , reading1, reading2 from lightsensordb.sensordatatable LIMIT 100

string to date:

date_parse(b.APIDT, '%Y-%m-%d')

transactions

If you are destroying and creating tables ofeten, tweaking and tuning, make a saved query for the create.

CREATE EXTERNAL TABLE IF NOT EXISTS billing.XXX (
  `posted` string,
  `payee` string,
  `address` string,
  `amount` float 
)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe'
WITH SERDEPROPERTIES (
  'serialization.format' = ',',
  'field.delim' = ','
) LOCATION 's3://XXX/XXX/'
TBLPROPERTIES (
 'has_encrypted_data'='false',
 'skip.header.line.count'='1'
);

SELECT date_parse(posted, '%m/%d/%Y') ,  payee FROM "billing"."XXX" limit 100;

transaction by day:

SELECT date_parse(posted, '%m/%d/%Y') as date ,  count(payee) FROM "billing"."XXX" GROUP by date_parse(posted, '%m/%d/%Y') limit 100;

if your data has a header remote it!

TBLPROPERTIES ( 'skip.header.line.count'='1');