amazon-redshift

问题 I am doing testing against AWS Redshift, and to replicate real world scenarios I need my test queries to not be cached so as not to give a false picture of performance. Is there any way for me to clear the Redshift cache between query runs? 回答1: I believe you can disable the cache for the testing sessions by setting the value enable_result_cache_for_session to off From the documentation If enable_result_cache_for_session is off, Amazon Redshift ignores the results cache and executes all

问题 I am doing testing against AWS Redshift, and to replicate real world scenarios I need my test queries to not be cached so as not to give a false picture of performance. Is there any way for me to clear the Redshift cache between query runs? 回答1: I believe you can disable the cache for the testing sessions by setting the value enable_result_cache_for_session to off From the documentation If enable_result_cache_for_session is off, Amazon Redshift ignores the results cache and executes all

问题 I am doing testing against AWS Redshift, and to replicate real world scenarios I need my test queries to not be cached so as not to give a false picture of performance. Is there any way for me to clear the Redshift cache between query runs? 回答1: I believe you can disable the cache for the testing sessions by setting the value enable_result_cache_for_session to off From the documentation If enable_result_cache_for_session is off, Amazon Redshift ignores the results cache and executes all

问题 When running the below query: WITH sublevels AS ( SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1), FIELDA AS (SELECT (ROW_NUMBER() OVER ())::INT sublevel FROM sublevels sl1, sublevels sl2, sublevels sl3) SELECT TOP 10 FIELDB, sublevel, REPLACE(REGEXP_REPLACE(REGEXP_SUBSTR(UPPER(FIELDC), 'FROM \\S+', 1, sublevel), 'FROM ', ''),')','') ALIASA FROM TABLEA JOIN FIELDA ON sublevel <= REGEXP_COUNT(UPPER(FIELDC), 'FROM ') WHERE ALIASA != 'ABC' AND lower(split_part(ALIASA, '.', 2)) IN ( SELECT

问题 When running the below query: WITH sublevels AS ( SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1), FIELDA AS (SELECT (ROW_NUMBER() OVER ())::INT sublevel FROM sublevels sl1, sublevels sl2, sublevels sl3) SELECT TOP 10 FIELDB, sublevel, REPLACE(REGEXP_REPLACE(REGEXP_SUBSTR(UPPER(FIELDC), 'FROM \\S+', 1, sublevel), 'FROM ', ''),')','') ALIASA FROM TABLEA JOIN FIELDA ON sublevel <= REGEXP_COUNT(UPPER(FIELDC), 'FROM ') WHERE ALIASA != 'ABC' AND lower(split_part(ALIASA, '.', 2)) IN ( SELECT

问题 When running the below query: WITH sublevels AS ( SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1), FIELDA AS (SELECT (ROW_NUMBER() OVER ())::INT sublevel FROM sublevels sl1, sublevels sl2, sublevels sl3) SELECT TOP 10 FIELDB, sublevel, REPLACE(REGEXP_REPLACE(REGEXP_SUBSTR(UPPER(FIELDC), 'FROM \\S+', 1, sublevel), 'FROM ', ''),')','') ALIASA FROM TABLEA JOIN FIELDA ON sublevel <= REGEXP_COUNT(UPPER(FIELDC), 'FROM ') WHERE ALIASA != 'ABC' AND lower(split_part(ALIASA, '.', 2)) IN ( SELECT

来源： https://stackoverflow.com/questions/60921001/internalerror-spectrum-scan-error-s3-to-redshift-copy-command

来源： https://stackoverflow.com/questions/63878541/column-has-unsupported-type-information-schema-sql-identifier

来源： https://stackoverflow.com/questions/54154325/how-to-do-a-stratified-random-sample-in-redshift

来源： https://stackoverflow.com/questions/54154325/how-to-do-a-stratified-random-sample-in-redshift