> DESCRIBE wmf_experiments.experiment_results_v1;
col_name	data_type	comment
dt	timestamp	When the experiment results were generated
experiment_name	string	Experiment owner-provided name of experiment
experiment_machine_name	string	Machine-readable experiment name, matchable with experiment_configs table
metric_name	string	
metric_type	string	Type of metric, used in reporting and formatting. Values: "Mean" or "Proportion"
difference_type	string	Difference types. Values: "Relative" or "Absolute"
user_auth_segment	string	For user segmentation by authentication status. Values: "Everyone", "Logged-in only", "Logged-out only"
sample_sizes	struct<control:bigint,treatment:bigint>	
sample_means	struct<control:double,treatment:double>	
sample_variances	struct<control:double,treatment:double>	
health_results	struct<p_value:double>	
bayesian_results	struct<estimate:double,variance:double,chance_to_win:double,loss:double,risk:double,credible_interval_95:struct<lower:double,upper:double>>	
frequentist_results	struct<estimate:double,standard_error:double,statistic:double,degrees_of_freedom:double,p_value:double,confidence_interval_95:struct<lower:double,upper:double>>	
		
# Partitioning		
Not partitioned

Database error
Failed to execute query 'SELECT *
FROM experiment_results_v1': 'NoneType' object is not iterable

select experiment_machine_name, sample_variances
from experiment_results_v1
where experiment_machine_name in ('fy24-25-we-1-7-rc-grouping-toggle', 'we-3-2-3-donate-ab-test-1')
order by experiment_machine_name;

experiment_machine_name	sample_variances
fy24-25-we-1-7-rc-grouping-toggle	{"control":null,"treatment":null}
we-3-2-3-donate-ab-test-1	NULL

USE bearloga;
CREATE TABLE experiment_results_v1_backup
USING ICEBERG
TBLPROPERTIES (
  'format-version' = '2',
  'write.delete.mode' = 'copy-on-write',
  'write.parquet.compression-codec' = 'zstd'
)
AS SELECT * FROM wmf_experiments.experiment_results_v1;

-- To test:
-- UPDATE experiment_results_v1_backup
-- SET sample_variances = STRUCT(NULL, NULL) WHERE sample_variances IS NULL;

UPDATE wmf_experiments.experiment_results_v1
SET sample_variances = STRUCT(NULL, NULL) WHERE sample_variances IS NULL;

USE bearloga;

CREATE TABLE update_test (
  `first_first` STRING,
  `last_name` STRING
)
USING ICEBERG
TBLPROPERTIES (
  'format-version' = '2',
  'write.delete.mode' = 'copy-on-write',
  'write.parquet.compression-codec' = 'zstd'
);

INSERT INTO update_test VALUES ('Peter', 'Parker'), ('Bruce', 'Wayne');

ALTER TABLE update_test
ADD COLUMN superhero struct<alias: string, powers: string>;

INSERT INTO update_test VALUES ('James', 'Howlett', NAMED_STRUCT('alias', 'Wolverine', 'powers', 'regeneration'));

SELECT * FROM bearloga.update_test

Database error
Failed to execute query 'SELECT *
FROM bearloga.update_test
': 'NoneType' object is not iterable

first_first	last_name	superhero
Peter	Parker	NULL
Bruce	Wayne	NULL
James	Howlett	{"alias":"Wolverine","powers":"regeneration"}

UPDATE update_test
SET superhero = STRUCT(NULL, NULL) WHERE superhero IS NULL;

first_first	last_name	superhero
James	Howlett	{"alias":"Wolverine","powers":"regeneration"}
Peter	Parker	{"alias":null,"powers":null}
Bruce	Wayne	{"alias":null,"powers":null}

DROP TABLE update_test;

hdfs dfs -rm -R /user/hive/warehouse/bearloga.db/update_test