How to Generate Date Series in Amazon Redshift Without generate_series()?

Generating Series in Redshift

Amazon Redshift is based on an older version of PostgreSQL (8.0.2) that lacks support for the generate_series() function when dealing with timestamps. Attempts to use the function with dates, such as:

select * from generate_series(date('2008-10-01'),date('2008-10-10 00:00:00'),1)

will result in an error.

Workarounds

Despite the lack of direct support for generate_series() with timestamps, there are a few workarounds:

1. Current Date Arithmetic:

SELECT current_date + (n || ' days')::interval
from generate_series (1, 30) n

This approach, which works in PostgreSQL 8.3 and later, uses simple date arithmetic to generate a series of dates.

2. Integer Table:

Create a table of integers that can be used for date arithmetic:

create table integers (
  n integer primary key
);

Populate the table and use it for date calculations:

select (current_date + n)
from integers
where n < 31;

Note: Redshift does not support the interval data type, so the above workarounds may not be available in all cases.

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