generate-series

When I run the SQL Query: select generate_series(0,g) from ( select date(date1) - date(date2) as g from mytable ; It returns an error: INFO: Function "generate_series(integer,integer)" not supported. ERROR: Specified types or functions (one per INFO message) not supported on Redshift tables. But when I run this query: select generate_series(0, g) from (select 5 as g) It returns the below response: generate_series ----------------- 0 1 2 3 4 5 (6 rows) Why does the second query work, while the first fails? The generate_series() function is not fully supported by Redshift. See the Unsupported

My app has a Events table with time-stamped events. I need to report the count of events during each of the most recent N time intervals. For different reports, the interval could be "each week" or "each day" or "each hour" or "each 15-minute interval". For example, a user can display how many orders they received each week, day, or hour, or quarter-hour. 1) My preference is to dynamically do a single SQL query (I'm using Postgres) that groups by an arbitrary time interval. Is there a way to do that? 2) An easy but ugly brute force way is to do a single query for all records within the start

I'd like to use the generate series function in redshift, but have not been successful. The redshift documentation says it's not supported. The following code does work: select * from generate_series(1,10,1) outputs: 1 2 3 ... 10 I'd like to do the same with dates. I've tried a number of variations, including: select * from generate_series(date('2008-10-01'),date('2008-10-10 00:00:00'),1) kicks out: ERROR: function generate_series(date, date, integer) does not exist Hint: No function matches the given name and argument types. You may need to add explicit type casts. [SQL State=42883] Also

Documentation for generate_series says that argument can be int or bigint for generate_series(start, stop) and generate_series(start, stop, step) cases and timestamp or timestamp with time zone for generate_series(start, stop, step interval) . What is the reason that generate_series works also with date type as input and returns timestamp with timezone ? pg=# select generate_series('2014-01-01'::date,'2014-01-02'::date,'1 day'); generate_series ------------------------ 2014-01-01 00:00:00+01 2014-01-02 00:00:00+01 (2 rows) Thanks to function type resolution we can also pass date values to

I am developing an algorithm with Postgres (PL/pgSQL) and I need to calculate the number of working hours between 2 timestamps, taking into account that weekends are not working and the rest of the days are counted only from 8am to 15pm. Examples: From Dec 3rd at 14pm to Dec 4th at 9am should count 2 hours: 3rd = 1, 4th = 1 From Dec 3rd at 15pm to Dec 7th at 8am should count 8 hours: 3rd = 0, 4th = 8, 5th = 0, 6th = 0, 7th = 0 It would be great to consider hour fractions as well. Erwin Brandstetter According to your question working hours are: Mo–Fr, 08:00–15:00 . Rounded results For just two