Sql of note: Difference between revisions
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* [http://sqlite.awardspace.info/syntax/sqlitepg06.htm|Great EXPLAIN and Example of JOIN] | * [http://sqlite.awardspace.info/syntax/sqlitepg06.htm|Great EXPLAIN and Example of JOIN] | ||
* [[Properties Table]] | * [[Properties Table]] | ||
== transpose wide tables == | |||
https://www.periscopedata.com/blog/using-row-numbering-and-full-joins-to-transpose-wide-tables | |||
== grouping == | |||
Redshift: | |||
https://docs.aws.amazon.com/redshift/latest/dg/r_Examples_of_avg_WF.html |
Revision as of 18:56, 14 September 2018
Example of Time bucket
select from_unixtime(timestamp-timestamp%3600)as time, count(*) from table where data like 'Destination directory %does not exist at%' and FROM_UNIXTIME(timestamp) > subdate(now(),interval 4 day) group by timestamp-timestamp%3600 order by time;
sqlite
.tables
.schema
Date / Time
These all return dates and times.
Last day of this month:
SELECT date('now','start of month','+1 month','-1 day');
the first day of this monnth:
SELECT date('now','start of month');
first day of last month:
SELECT date('now','start of month','-1 month');
last day of last month:
SELECT date('now','start of month','-1 day');
get epoch:
select strftime( '%s' , "2012-09-30") ;
convert from epoch to date:
SELECT datetime( 1092941466 , 'unixepoch');
convert back and forth:
SELECT datetime( strftime( '%s' , "2012-09-30") , 'unixepoch');
X in Y
SELECT filename FROM source WHERE hash NOT IN (SELECT hash FROM destination);
Also see
transpose wide tables
https://www.periscopedata.com/blog/using-row-numbering-and-full-joins-to-transpose-wide-tables
grouping
Redshift:
https://docs.aws.amazon.com/redshift/latest/dg/r_Examples_of_avg_WF.html