A date dimension is a typical case for data generation. Tabulify provides one date dimension that you can use out of the box and modify to your needs.
The date_dim–generator.yml is a generator where::
kind: generator
spec:
Comment: An example of date dimension generator based on the `date_dim` table of TPCDS
primary-columns: [ "d_date_sk" ]
Columns:
- name: d_date_sk
comment: A surrogate key
Type: integer
data-supplier:
type: sequence
- name: d_date
comment: A business key in date format
Type: date
data-supplier:
type: sequence
arguments:
start: 2025-05-13
- name: d_date_id
comment: A business key in string
Type: varchar
data-supplier:
type: expression
arguments:
column-variable: d_date
expression: "d_date.toISOString().substring(0,10)"
- name: d_month_seq
comment: An ascendant sequence for the month
Type: integer
data-supplier:
type: expression
arguments:
column-variable: d_date
expression: "function pad(number) {if (number < 10) { return '0' + number; } return number; }; d_date.getFullYear()+''+(pad(d_date.getMonth()+1))"
- name: d_day_name
comment: The name of the day
Type: varchar
data-supplier:
type: expression
arguments:
column-variable: d_date
expression: "var days = ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday']; days[d_date.getDay()]"
- name: d_moy
comment: the month number in year
Type: Integer
data-supplier:
type: expression
arguments:
column-variable: d_date
expression: "d_date.getMonth()+1"
- name: d_year
comment: The year number
Type: Integer
data-supplier:
type: expression
arguments:
column-variable: d_date
expression: "d_date.getFullYear()"
With the data head command and the howto directory connection, you can test your generator and see the data.
tabul data head date_dim--generator.yml@howto
The first 10 rows of the data resource (date_dim@memgen):
d_date_sk d_date d_date_id d_month_seq d_day_name d_moy d_year
--------- ---------- ---------- ----------- ---------- ----- ------
1 2025-05-12 2025-05-12 202505 Monday 5 2025
2 2025-05-11 2025-05-11 202505 Sunday 5 2025
3 2025-05-10 2025-05-10 202505 Saturday 5 2025
4 2025-05-09 2025-05-09 202505 Friday 5 2025
5 2025-05-08 2025-05-08 202505 Thursday 5 2025
6 2025-05-07 2025-05-07 202505 Wednesday 5 2025
7 2025-05-06 2025-05-06 202505 Tuesday 5 2025
8 2025-05-05 2025-05-05 202505 Monday 5 2025
9 2025-05-04 2025-05-04 202505 Sunday 5 2025
10 2025-05-03 2025-05-03 202505 Saturday 5 2025
If you want to know how to create a CSV from it, check the below page